Our new tow vehicle and people hauler. We bought it used from Raridon Dodge out in Monroe, WA. It's quite well equipped with a 5.7L V8, and pretty much every option they offered on a Suburban in 1999 other than a big block and the 3/4 ton setup.
Manual 4x4 shifter
Seats and interior
Engine compartment sticker
Door pillar sticker
Glove box sticker with all the option codes listed. I have most of them decoded in a section further down on this page..
The left rear brake drum. Note junk-yard-style writing on it saying "4x4 1998 Sub" - this was a big clue for the problem that led to the rear axle work; see Rear Axle section below for details.
I helped with pulling some stumps at a friend's house after he blew out one of the front hubs on his monster F350. My tow hooks are way lighter duty that his are, but his truck also outweighs and out powers mine by about 30%. Gotta love that turbo diesel 7.3L in his rig. Anyways, I was able to pull my truck in the hole we dug with his tractor and finish off the pulling duties without any major trauma. Looking out the window and being level with the surrounding ground was more than a little weird, though.
During some of the wiring work (see down below) on the fog and driving lights, my daughter was pretending to drive. It was cute enough to take a picture...
Can you tell what's wrong in this picture? Hint: Look closely at the manual release on the garage door opener. I had pulled the truck into a friend's garage to work on the wiring, and when I went to put the door down, this is what happened. The red release handle got trapped under the roof rack, and perfectly unlatched the door from the opener track, and managed to get the handle jammed between the roof rack and the roof of the truck. I have such great luck at times... I thought it was amusing enough to share...
Some pics of the new and improved front lighting during a snowstorm. I think it's very cool looking, and it's super functional. The first two are on low beam with the driving lights manually turned on, and the last two are on high beam (note the difference in the headlights) with the fog lights manually turned back on. The last one is the best shot of the bunch, in my opinion.
I finally got the front door windows tinted, and here are the pics. This helps with heat gain, glare, and best of all - it looks cool! :-)
What, you thought I'd be leaving it alone? Not. Anything needs work at some point or another... Besides, some of this was part of what got me a good price on the truck. Here's what I've done on the truck since getting it:
Stuff that needs doing:
Before I bought the truck, I tried out the 4x4 setup in a gravel lot and it worked fine. After I bought it I tried it on pavement - and something was clearly amiss. The whole front end galloped and bucked at even 5mph and things were clearly not right. What was wrong? Apparently the previous owners had swapped out the optional 3.73 ratio non-posi rear for a standard 3.42 ratio posi rear - but had not changed the front diff to match the new ratio in the rear. Great news on upgrading to the posi, but having mismatched front and rear ratios made the 4x4 setup useless for street use, the posi unit they picked was a style with an internal governor that is known to explode the carrier assembly under sudden shock loads, and the standard ratio rear had a lower towing capacity. Not cool! So, I opted to have a local shop - NW Differential - rebuild the rear axle completely with an Auburn posi in the correct 3.73 ratio - and man, rear axles are expensive to rebuild! They found out one of the axles was worn under the bearing surface, so I replaced that while I was in there. $1900 later, and it's much happier now, and much peppier too. At least the speedometer was still set up for the original 3.73 ratio, so I didn't have to adjust that once I fixed the ratio to be correct...
Incidentally, NW Differential is the same shop that rebuild the rear axle in my 1975 Suburban many years ago, and it's still going strong. They were great people to work with both times, and did great work, so they have a good reputation with me. They are the first place I go for any rear axle work. You should too. Yes, rear axle work is pricey - your wallet will hurt no matter where you have the work done. That's why a quality shop is a really important thing. You really don't want to pay for a rear axle rebuild more than once. Do I get a discount on my next rear axle rebuild for the free advertising? :-)
Lesson learned: Testing a 4x4 setup on gravel and not on pavement will let the mis-matched ratio issue hide because the gravel slips easily under the tires at low speeds and the pavement doesn't give at all. Even at 5mph it's plenty clear what's wrong. Doh! My fault all the way, and I suspect the dealer had no idea.
The truck had 160,000 miles on it when I bought is, so the factory wear items in the front suspension are either already due for replacement, or will be coming due soon. I knew this when I bought it - it's just part of the deal with a higher mileage vehicle. The truck was quite drivable as-bought, but it was not perfect. The main issue was some highway vibration about 65mph. These are all getting addressed as I have time.
The first in this list was the idler arm. It's conceptually very easy - three bolts holding it to the frame and one ball joint connecting to the center link. Yeah, not so much.
The pitman arm needed replacement, and I got tired of waiting for my schedule and good weather to align, so I had it done at a shop. It was going to be a chore - I had to buy a special compact pitman arm puller for it due to limited clearance, and I never even got to use my spiffy new tool. You have to unbolt the steering box to get the clearance to use the puller. Whee! Another "way to go, Chevy" design...
Driver's Side Ball Joints
The drivers side ball joints also needed replacement, and as with the pitman arm, I got tired of waiting for my schedule and good weather to align, so I had it done at a shop. Meh.
After the idler arm, pitman arm, and ball joints were changed, I got new tires all around and had the truck aligned. It's much nicer on the highway now - no weird vibrations above 60mph. Whee!
Daytime Running Light Disable
Like may other folks, I really don't like the GM daytime running lights (DRL) that they force on you in all of the newer GM vehicles. The studies purporting to show a decrease in accidents are questionable at best, and in reality it doesn't help. And, in some cases, it's downright dangerous, like in heavy fog. Did I forget to mention that here in the USA it's not legally required to have the DRL's? GM tried to get it passed into the regulations, and the feds told 'em to take a hike because it wasn't going to increase safety. So, I researched how to disable them on this particular vehicle, and did it myself. I know how to drive and I'll turn my lights on when I want them on, thank you very much. If you're a safety nut and think DRL's actually help, well, I'm sorry you're not capable of independent thought anymore, and are not taking responsibility for operating your vehicle safely. I am, and I do.
Anyways, the actual disable turned out to be pretty easy - there's a small module under the dash that is used as a glorified relay to provide power to the low beams when the DRL system wants them to turn on. Unplug that module, and you have no daytime running lights anymore. The dash indicator light stays on, but you can remove the bulb from that easily enough. The module is just a massive heat sink with some solid state devices inside of it, and a small electrical plug on one end. It's mounted under the dash just above the accelerator pedal and is easy to see when you look up under the dash and know what to look for - nothing else looks like it. In my case, the trailer brake controller and my MP3 player hookup device were in the way, so I had to work around them, but it wasn't a big deal.
The under-dash pictures are somewhat out of focus, but you'll get the idea. There are two tabs on the mounting bracket that you have to bend back, and then you can wiggle the module around so slide down and out of the bracket. Depress the plastic tab on the electrical plug and it will unplug from the wiring and can be removed. I just tossed it in the glove box in case the next owner really wants the DRL setup to work again. Whatever.
Disabling the indicator light was simple - pull the trim piece around the cluster + radio (held on with spring clips and pulls off with no tools), pull the cluster (four bolts), and remove the DRL indicator bulb from the back of the cluster. Pull the bulb out from the little plastic socket, reinstall the socket to keep light and dust out of the back of the cluster, and then re-install the cluster and the trim. to get to and remove. It's a light green indicator, but for me it was hidden behind the steering wheel most of the time, so it was not very distracting, but it was enough. In my case, the bulb had virtually fused itself to the metal tabs in the bottom of the little plastic socket, so I had to break the bulb with pliers and chip out the remnants with a jewelers screwdriver. By that point it had annoyed me enough that I Was Going To Win™, and I did.
Random trivia: Supposedly if you buy a GM vehicle new, you can request that the DRL's be disabled before you take possession of the vehicle and make it a condition of the sale. They will typically give you the runaround and sometimes even lie and tell you that it's legally required, but they can do the disable if you lean on them. Some export models can't have DRL's, so there's going to be a way to disable it, and they can deal with figuring out how. Some folks have even reported there is a specific option code to disable the DRL's.
Looking at the dash from the driver's seat, it's just above the accelerator pedal area, tucked up against the lower edge of the dash. I added labels in red to help you figure out the pictures.
This is the module itself. Good riddance. It's now cluttering up my glove box just so I can sell it with the vehicle in the future. I may hate 'em but the next buyer might think they rock. Meh. I save old parts...
Zune Mount and Hookup
I like my tunes, and I don't want to carry around a stack of CD's, so both my wife and I have Zune. I can't stand Apple's iTunes software, and I'm a Microsoft guy anyway, so the Zune works for me. To hook up the Zune in this vehicle, I opted to installed an FM modulator under the dash to provide a hookup for the audio and to built a mount for a Zune dock in the center console, where the CD storage normally goes. A small switch is located on the bottom edge of the dash to turn the FM modulator on and off; with it on, I get no AM reception, so the switch has to be reasonably easy to reach. The audio cable runs from inside the center console, under the carpet, and up under the dash, and there is a power wire running from under the dash to the center console - oddly enough, there was no wiring whatsoever in the console, so nothing to tap into.
The dock needs a USB power supply to run, so I got a USB Type A jack with bare wires from L-Com and wired it in. To wire it up with 5V power, I used a simple 7805 transistor - the whole idea came from a tech article on this in Rod and Custom Magazine. The transistor and USB jack were mounted in the base on the console so they were accessible once the center tray section of the console was removed, but hidden from view when the console was assembled. There was a nice metal brace on the base of the console that I mounted the transistor to for a heat sink, and a piece of the inner plastic support for the console provided a perfect place to mount the USB jack. One of the console mounting bolts made the perfect place for a ring terminal to ground the USB power. Everything has wiring disconnects on it so it can be easily removed when the console needs to be removed for service.
The mounting pad I made for the Zune to sit in the front CD holder area of the center console uses some simple plywood sheets, with a lot of filing and sanding, some wood filler, and a lot of painting to shape the top to a reasonable curve to match the console and give it a smooth finish. I sanded the primer coats like it was a auto body repair to get it smooth. It mounts in the CD holder area. The CD holder tray is still down there, with 2 pieces of plywood cut to match CD case dimensions and set into two of the four CD slots. I simple removed the top "door" that is used to cover the CD's. The top piece of plywood is then nailed and glued to the vertical plywood pieces in the CD slots. The Zune mount itself is simply held onto the top piece of plywood with a piece of Velcro. There is a small slot in the front center of the top piece of plywood to allow the USB and audio cords to get down into the CD holder area, and the vertical pieces of plywood in the CD slots have notches cut in the bottom so the cords can lay on the bottom of the CD holder area without getting pinched. I cut a small discreet hole into the base of the CD holder to allow the USB and audio cables to snake down into the base of the console, where I can plug into the USB jack I installed down there and the audio cable can be plugged into the one that goes up to the FM modulator under the dash. It's simple, cheap, and looks pretty decent for the effort I put into it. And, if need be, I can remove it and re-install the CD cover piece when I sell the truck, and no visible damage has been done to the console itself. The top board isn't cut and shaped quite perfectly, and the top board isn't mounted to the inner vertical support pieces quite as straight as I'd have liked. The board slipped a bit while being nailed into place, unfortunately. All in all, it's a nice setup and it works well, and I can take the expensive piece of hardware - aka, the Zune - with me when I park the car, so it's not a theft target. It's also very easy to reach the Zune while driving and change songs and the like.
My only complaint is the Zune dock itself - it's the normal "home use" dock, and it's designed to grab the Zune outputs and play them through non-amplified speakers, or hook up to a PC via the USB cable. The audio outputs are not a digital converted to line out like a car adaptor is, rather, they are the volume controlled Zune outputs much the same as plugging in the headphone jack. That means the volume control on the Zune itself is still in play, and the sound is distorted if you crank the volume all the way up on the Zune itself. It also means the Zune screen goes dark after a few seconds of inactivity, at least with the settings I've got on it that work well in my other vehicles. Not the end of the world, but not perfect either. I was never able to find a true "car dock" for the Zune, which is unfortunate. It's a good player and works well, it just doesn't have the aftermarket support of some other brands.
After getting it hooked up and in use, I discovered that the Zune would power up when the USB jack had power, but it would not charge the Zune from it and it would slowly discharge the Zune while it was in use. The cause was a mystery to me for a while, so I just lived with it - there was enough juice present that it took a couple of weeks to discharge the Zune in normal driving to and from work, so I lived with it for a while until it annoyed me enough to research it and figure it out. While doing that research, I found a great article by a guy who was trying to make a small USB charger called the Mintyboost and his trials and issue getting it to charge a high drain device, and that gave me pretty much all the info I needed. The diagram at the bottom of the second page shows the trick - you need to put 2V onto both data lines, and that will essentially tell the USB device "it's OK to pull some power out of this USB port at a reasonable rate". It's really simple - a simple 2 resistor voltage divider takes the +5V USB feed and splits it to provide a 2V feed for the data lines. I simplified that diagram a bit and used only two resistors feeding both data lines, and it seems to work fine. My understanding is that the resistor values can be many different ones, so long as the voltage divider outputs close to 2V and isn't drawing any noticeable power. I bought an assorted pack of resistors at Radio Shack and found two that would work using an online voltage divider calculator - I think I used a 5K and 3.3K resistor from the assorted pack and I think it came out at 1.987V or something like that. So far it's working for me; your mileage may vary. If you decide to do this, it's a "do it at your own risk" sort of thing.
Let There Be Light!
The factory headlights on this truck are not super bright. They're OK, but not great. And making it worse, the lenses are dirty and need a deep cleaning. That makes night time driving away from populated areas less enjoyable than it could be. So, to fix that, and to dress up the front of the truck a bit, I bought a few things from Amazon and JC Whitney.
The headlight cleaning kit is an easy and obvious "duh" item, I just need to get around to using it. :-) The fog and driving lamps will net a large increase in usable light when driving at night, and the grill guard should improve the looks of the truck and give me a good place to mount the driving lamps up nice and high so they throw light way down the road. The fog lamps will be mounted at the outside edges of the underside of the front bumper to get them reasonably close to the road without being completely in the way. The backup lamps help when backing up, especially when working with a trailer at night.
At a minimum, I'm going to wire the fog and driving lights in the normal (and legal to use on the street) fashion - they are either off, or the fog lamps are on with the driving lights and/or low beams, and the driving lights can only come on with the high beams. If I can find the right lighted SPDT switches to use, I'm going to also wire them to be able to be on all the time, for those situations where you just want a small supernova on the front bumper lighting your path... That's obviously not for normal highway driving, though.
The backup lights will be wired to either be off, or to come on with the normal backup lights. Again, if I can find the right lighted SPDT switch (same as for the fog and driving lights) then I'll also be able to wire the backup lights to be on anytime. That's helpful when you are working on something behind the truck and need extra light. As with the fog and driving lights "always on" feature, this is not for normal usage as turning on rear-facing 55W clear lights is 1) illegal to do while out on the highway and 2) not very nice to your the other drivers on the road. I've used these same backup lights before on my 1975 Suburban. They are easy to mount, easy to wire (well, you do have to run one wire down the length of the frame...), and they work very well. They're also cheap and pretty durable. I like them so much, I'm planning to put a set on my 1986 Ford F250 as well when I have time...
I found the right switches for this via Waytek Wiring, but they are funky to wire to get it to work right. The basic switch is Waytek part #44326, and you have to buy the actuator (the part you touch and move to flip the switch to a different position) with the desired lens color in it - Waytek #44371 is a blue lens, #44353 is an amber lens, #44352 is red lens, and #44354 is a green lens. You'll also want the wiring connector - Waytek #44836 - and the wiring terminals - Waytek #31090 is the terminal for 14-16 gauge wires, which is fine for anything driving a relay. You may also want to get Waytek #44381 so you can remove the actuators from the switch bodies. The switches are DPDT center off switches with a dependent pilot light. They assume you will wire them as power into the middle/common post and output power through either of the two throws. The lights each wire from one of the poles to a common light ground. In this case, I really only want one light (because that's all I could get for the lenses in the desired colors), and I want to wire the switches "backwards" from their intended usage. In my case, it's two different power feeds being wired to one common output. This works fine, since the light in the switch is only wired to one of the poles, and it's a double pole switch. I can use one pole for the actual power switching, and then connect the switch output to the same terminal on the other pole that drives the light I want to use. Basically, out of the seven contacts on the switch, I only use five, and I used one of them "backwards" as the input to the light instead of the output from the switch. It's weird and took me a while to figure out, but it works, the switches are reasonably priced, nice looking, reliable, have a good "feel" to the switch as it operates, have all the wiring bits readily available, and have good color choices on the lenses. Sold!
If needed, I can adjust the brightness on the pilot light via an inline resistor on the grounding side of the light. This way they won't be super blinding at night.
Here are some exceptionally fuzzy pictures of the tests I ran on the switch to see how the indicator light looked and how to wire it. The night I did this, it was late, and I couldn't sleep, and I had just figured out how to make it work - the proverbial "Ah-hah!" moment. Great for verifying this, but because it was 45 degrees in my garage and I was quite cold, there was no way I was going to get a decent picture of it. Meh. It's good enough to document what I needed to remember.
Pilot light off:
Pilot light on:
Wiring for pilot light - the terminal on top is the feed for the light, and the one to the bottom right is the ground for the light. The other three terminals on the bottom are for the pole that will be used to do the real work on the switching. I'll have a jumper from the middle bottom to the upper right to provide power to the light.
Here's the wiring diagram for adding the fog, driving, and extra backup lights. The under-dash wiring can be done as one harness and the switches and one under-dash relay installed in whatever room there is. I'll need to tap into a few existing things for +12V power and for trigger wires for the parking lights (not low beams - this way the fog lights come on with only the parking lights on), high beams, and existing backup lights. The one relay is there to turn off the fog lights when you switch to high beams. This makes them legal so the fog lights are only on with low beams or alone. Having them on alone is useful when it really is foggy out. You want just the fog lights in that case to get the light "under" the fog and reduce glare. Turning the fog lights on with your low beams pretty much defeats the purpose of the fog lights in the first place and makes them simply auxiliary headlights. Useful, but not for their intended purpose. This small wiring tweak makes them much more useful for minimal additional work, and keeps them legal.
This particular era of GM truck has a really annoying factory wiring setup for the headlights. It's a 4-headlight system, but the low beams turn off completely when the high beams are on. That's a waste and limits the overall high beam light output. As part of this setup, they use single-filament bulbs for both the low and high beam bulbs. There are a number of relay kits out there to turn the low beam lights on with the high beams, but they all re-use all of the factory wiring, and they don't provide a high power feed for the headlights.
The diagram below shows how to do a full-on rewiring for the headlights for larger wires, to get the low beams to come on with the high beams, and to get the high power feed. Basically, this is the modification described at Wiring Headlight Relays, with a small twist to get the low beams to come on with the high beams. In the diagram, you'll note that there is a diode connecting the high beam to the low beam wires that will serve as the relay coil/trigger/input wires. This is done so that when the high beam wire has power, the low beam wire will also, but not the reverse. For the electronically allergic, diodes are a small device that only allows one-way current flow. That can be very handy in places. Note the way they are wired - they are one-way valves for electricity, and they are important to diagram and wire in the correct direction, or stuff won't work right.
When I wire this, I'm going to to skip the full on rewiring to the headlights and re-use the factory harness wiring for that. You may wish to go full tilt on your wiring, so I'm showing it that way. In my case, I'm basically going to find a place in the factory wiring harness just upstream of the factory splices for the left and right headlight wires (it's near the front corner of the computer on the driver's side inner fender), and cut the tan and green wires there. I'll install a pair of matching male/female two place WeatherPak connectors there so that I can plug them together and bypass the relays if needed - say, if I sell the truck and want to take my relays and such with me for the next truck. The wiring to the relays will use the same connectors so it all just plugs in with minimal disruption to the factory wiring. The rest of the wiring will be new and in a separate sub-harness, but done in a factory-like manner so it's all easy to remove later if needed for service, or total removal whenever I sell the truck.
This is the same basic diagram as the previous one, but with the headlights wired into relays as described above. It also shows the circuit breakers for the high power feeds to the relays. They ought to be there in the previous diagram as well, but I left them out for no good reasons that I can think of. But, you're smart enough to use circuit breakers or fuses on all of your power feeds, right? Good. I thought so. Stay safe, wire smart.
More improvements, this time allowing for a later brightness control box for the indicator lights in the switches. Basically, I ran all three of the indicator light grounds as individual wires in the harness back to a common and easily accessible point, along with a wire that was directly grounded and a wire from the parking light feed. For the initial work, I just tied all three indicator light grounds together with the real ground and it works. Later, I'll builds the control box described below to improve on things. Having the parking light feed available to the brightness control box allows it to react to the dash lights being on to dim the indicator lights even further so they are visible during the day but not blindingly bright at night.
Indicator Light Brightness Control Box
Here's a simple version of the control box wiring that I'm starting out with. Basically, three adjustable resistors, one per light, to control the "daytime" brightness of the indicator lights. To allowing for variances in light output and lens color (some colors may be perceived as brighter than others), each light has a way to dim it down. The relay switches is set up so that normally, the three resistors are connected directly to ground, but when the parking lights/dash lights come on, all three indicator lights go through an extra adjustable resistor so I can dim them all a fixed amount when the dash lights are on. These adjustments are intended to be set once and then ignored forever, so they are inside a small control box that will be mounted under the dash. I can adjust them once on install to whatever I want, and then ignore it forever. If I change out a bulb in the switches and it's slightly different in brightness, then I can re-adjust the control box if needed, though I doubt that will be necessary. Having adjustable resistors means I don't have to worry about figuring out the perfect resistor before installing everything, I can build the box with a reasonably sized resistor and adjust it later.
For reference, the bulbs in my switches were 19-20 ohms in resistance. Heading over to my Wire Capacity Chart page, I have a bunch of handy info to calculate what's going on in the indicator light circuits. Using this in a voltage drop calculator I've linked to, you find out that assuming a 14 volt feed, that 20 ohm light draws 0.7 amps and 9.8 watts of power. Adding the extra inline adjustable resistors basically creates a voltage divider, and there are online voltage divider calculators to play around and figure out roughly what sort of resistance value I'll need.
If I used a full 20 ohm resistor as the variable resistor, I'd basically cut the voltage in half for the pilot light to approximately 7 volts from the full 14 volts (actually 14.6V at the battery when the engine is running, but assume some voltage loss in the system already and round down to 14V), and reduce it's light output dramatically. It will also drop the amperage at the bulb to .35 amps and the wattage to 2.45 watts. So, while that may be way overkill for the three brightness trimming resistors, it's in the range for a reasonable choice for the "dash lights are on" dimming resistor. Since I'd be aggregating three bulbs into one variable resistor, that one would need to have enough capacity for 1.5A (.35A x 3 + safety factor) and 10 watts (2.45 watts x 3 + safety factor). For reference, bumping it up to 30 ohms leaves just 5.6V for the indicator light, which is likely too much dimming, though it can be adjusted down, the range of adjustment might not have much fine-grained control on it. Dropping it to 10 ohms means a maximum of 9.3V for the indicator light. That makes the amperage and wattage requirements on the "dash lights are on" a dropping resistor rated at 1.5A (.465A x 3 + safety factor, basically unchanged from before) and 15 watts (4.33 watts x 3 + safety factor, slightly bigger than before).
For the brightness trimming resistors, something more in the 10 ohm range might be more sane, but that might not be readily available at my local Radio Shack, though I could order some stuff in from someplace like Digikey if I wanted to wade through their enormous catalog and wait for shipping. However, Radio shack does stock a decent 25 ohm potentiometer rated at 3 watts in stock at most stores, so I'm likely going to get four of them and give that a try.
For the relay, something rated at 1.5A should be fine, so long as it's a single pole double throw relay. They have cheap PC board mounted relays available at Radio Shack as well.
Radio Shack also sells small PC boards and project cases too, so I'll go see what I can find there.
As part of this, you may want to refer to my relay wiring guide.
Headlight Wiring Plug
As described above, I installed a pair of 2-terminal WeatherPak connectors inline in the factory headlight wiring. This way I can easily plug in my new lighting harness and not have any issues, and still remove my wiring later on if I need to.
As part of doing this, I found out that the factory wiring is a puny 16 gauge wire. Yikes! I may decide to rewire the headlights all the way out to the bulbs after all... We'll see how it works out with the relays boosting the voltage to the headlights and after I clean the lenses...
The factory wiring loom on the driver's side inner fender. The tray is there for a second battery option, which my truck does not have. I'll be mounting the relays and circuit breakers for the new lighting harness on the vertical part of the inner fender you can see here. In this picture, I have already removed the loom from the two plastic holders in this area, and started to pull the wires out of the split loom to confirm where the factory splices are located at. The splices are where the two individual wires from the headlight dimmer switch for the high beam (light green) and low beam (tan) each split into two wires to go out to each headlight. I need to be "upstream" of those splices so I provide power to both headlights from the relays.
This is after I pulled the split loom completely off of this section of the harness and moved it out of the way, and installed the connector in the light green and tan wires. You can clearly see the connector on the left and the two splices off to the right, closer to the headlights. I believe the factory connector at the top by the fender is for the wires that go to the washer pump. After I cut the light green and tan wires, I unraveled them from the rest of the harness and put them back in so that it would be easy for this new connector to stay outside of the split wiring loom. That's why they are "off to the side" from the other wires here. This is important to be able to do the crimping work on the terminals in the connector, and for re-assembling the harness later on.
This is an up-close view of the new WeatherPak connector from the other side, after taping the wires in the harness together at a few critical points to ensure things didn't come unraveled. I had to replicate the factory sticky tape around where the washer pump wiring came out of the harness, since I had to remove it to see all the individual wires to get all this done.
This is the harness after having the split loom put back onto it. I decided to put a few spots of tape on it to ensure it stayed together in critical places. After a few months, it will self-form to the new changes and stay in place, but the tape will ensure it stays put for those first few months. After it's dirty, you'll never notice it's there.
This is the harness after being rotated to put the new connector "down" and out of the way of the hood, and after placing the harness back into the plastic clips that hold it to the fender. It pays to be careful when removing the harness from these clips, as now it fits back where it belongs without any issues. For now, the new connector is simply plugged together to get power to the headlights the same way the factory intended to. Later on, this connector will be opened and each side connected to the new wiring harness. The left side of the connector (the side with power from the dimmer switch) will power the high and low beam relay coils, and the high power output from the relays will be connected back tot he right side of this connector (the side that connects to the headlights).
If you look closely, you can see a series of small black dots on the inner fender - that's where the circuit breakers and relays will be mounted at. Each relay mounts with individual screws (5 screws total - the top line of dots) and the circuit breaker bracket has a mounting screw at each end (the lower larger dots). The wiring going down to the washer pump is wrapped onto the hose from the pump - that's the black hose heading left and underneath the bracket attached to the fender. The circuit breakers will sit behind that tubing when they are final mounted. It's not clear in the picture, but there is plenty of room between it and the fender for this.
Engine Compartment Wiring Harness
This is the starts of the engine compartment wiring harness for the auxiliary lighting. I measured for the relative mounting positions for the relays and the circuit breakers, as they are the primary fixed points that I needed to deal with here. Then, I mounted them to a board that I could lay next to the truck and work on more easily than being bent over the engine compartment. I ran all the wires that I could, and left most of the wires long to be cut to length on the truck. I'll put non-sticky harness tape on this bit of the harness before I install it so the wires stay put.
The long large red wire on the right is the main power feed from the battery. The large blue wire on the right is the high power wire to the driving lights. The large yellow fog light wire has yet to be installed at this point.
A close-up of the relays and circuit breakers. As in the previous photo, the long large red wire on the right is the main power feed from the battery. The large blue wire on the right is the high power wire to the driving lights. The large yellow fog light wire has yet to be installed at this point. The large purple wire is the high power feed to the backup lights. It will connect to a wire I installed that comes up the length of the frame from the backup lights.
You can clearly see the relay coil ground that will be installed to the forward mounting bolt for the circuit breaker mounting bracket. The daisy-chained small black wires from each relay are the relay coil grounds - they don't take much power and can be a small wire. It makes getting two wires into each terminal much easier.
The small yellow, blue, and purple wires heading off to the right are the trigger wires for the fog, driving, and backup lights. They will be terminated in a connector over near the firewall, and later will be connected to the under-dash harness I will build for this.
There are two sets of light green and tan wires. These will connect to the newly installed in-line connector in the factory headlight harness. The longer pair of light green and tan wires at the top is the high power output to the headlights. The short pair of light green and tan wires at the bottom is the input to the relay coils form the headlight dimmer switch. If you look carefully, you can see the heat-shrink-wrapped diode installed between the high and low beam relay coil feeds. This diode is what ensures that the low beams stay on when the high beams are turned on. It simply allows the high beam relay coil wire to power the low beam relay coil, but not allowing the reverse to happen. As noted previously, for the electronically allergic, a diode is just a one-way valve for electricity.
You can see the buss bar installed on the circuit breakers to make it much easier to get power to all four of them. The main power wire is a bit of overkill - 8 gauge. No power drop there... :-)
You may be wondering why I have four circuit breakers and five relays. That's because the two headlight relays will draw power from the same circuit breaker - the right most one in this picture.
The fog light power feed has been installed at this point, and I put a very noticeable bend in the ends of the tan and green wires that are the "trigger" wires that connect to the dimmer switch side of the harness. I did that and took a picture as a memory aid to remind myself which one was which as I moved on to further work. At this point I had yet to install the connectors on the short red wires to connect them to the circuit breakers, though you can see the yellow connectors sitting on the table to the left and below the circuit breakers.
While I was working, my daughter grabbed my cell phone and proceeded to take a bunch of random pictures of me working on this. Some are useful, some are just entertaining (a shot of my backside? Really? *sigh* Kids these days...), but they're fun enough to post. What she managed to get some pictures of was the work I did to ensure good routing of the harness along the inner fender. I removed the computer and leaned it out of the way, and by removing one bolt, I could do the same with the under-hood fuse and relay center. This allowed me to run the harness towards the firewall in a much more direct and out of the way fashion, which was nice. I'll be able to get the connector for the trigger wires to be inside the cab, which is better for moisture and what not. It will also make building the under-dash harness easier, since I will be able to do that without lifting the hood for the final hookups. Moving the fuse and relay center is a pain, and there it a rats nest of wires up by the firewall on the driver's side.
I removed the entire grill assembly for access to run the wires along the top of the bumper to get to the lights themselves. It comes off as one big unit after removing only 5 small bolts and pulling the parking light sockets + bulbs from the parking light housings. GM did a very a very nice job of engineering on this one. It's very easy to get in there for service. The grill guard makes it a bit harder to get on and off, that's my fault, not GM's.
Anyways, by doing this, I could tie-wrap the new harness to the factory harness that runs along here and ensure it was safe and out of the way. I put in simple two place connectors here for each light, and ran individual grounding wires from each light back to a common grounding screw for each side.
This is the driver's side. You can see the driving light connector with the blue wire going into it poking up next to the AC condenser, the grounding screw for this side about in the middle, of the fog light connector with the yellow wire going into it behind the parking light bulbs. Oh, and while doing this, I found out that the side marker light bulb on this side was burned out; I need to remember to replace that bulbs when I go to hook up the fog light on this side...
This is the harness on the driver's side in front of the radiator and AC condenser. It's a bit out of focus, but it's easy enough to sort out where the shiny new black harness is and how it's tie-wrapped to the existing harness to keep it out of the way.
This is the passenger's side of the radiator, and the factory harness plus my new harness run underneath of the transmission cooler lines to keep them safe and out of the way - you can just see my new harness below and to the right of the transmission cooler. If pops up to the left of this photo, see the next photo for details.
This is the passenger's side light connectors. For reference, the passenger's side headlight is cut off at the top of the photo, and the edge of the transmission cooler from the previous photograph is cut off on the far right edge of the photo. The driving light connector is visible poking up just in front of the AC condenser lines - the new harness is following the factory harness and is behind the plastic valence panel and out of sight at this point. You can just make out the blue wire going into it if you look really closely. The new ground screw for this side is visible behind the parking light bulbs, and the fog light connection with the yellow wire going into it is clearly visible on the left side of the photo.
This is the new 8 gauge power lead to the circuit breakers. It follows the main power lead to the under hood fuse and relay center, and will go the factory installed "mega-fuse" that connects the alternator to the battery. You can see where the factory power wire takes a sharp dive down just behind the coiled up section of new red wire - that's the mega fuse. I didn't have the right side terminal at this point, so that's one more trip to NAPA for some parts, and why the excess red wire is coiled up and out of the way here. The grill is laying on top of the engine at this point.
This is the relay and circuit breaker assembly installed on the driver's side inner fender. You can clearly see where everything sits at, and you can now clearly see the yellow connectors for the short red wires at the circuit breakers, as well as the way the front two relays share the same power feed. The red wires ended up a bit bent because I had to adjust the relay mounting a bit to fit over some stampings in the inner fender, and tilt the front edge down a bit to fit under the factory harness better. All in all, it's not a bad looking setup for a fairly cramped install. You can see the shiny new harness going between the relays and the circuit breakers. The right side of the new harness goes through the radiator core support and out along the bottom edge of the radiator, see the previous pictures for more details. The left side of the new harness goes under the computer and under hood fuse and relay center to toe firewall, again, see previous pictures. The large red wire is the new main power feed for this. I may decide to cover the 8 guage red power lead it in some split-loom to make it blend in better and give it better chafing protection.
The unconnected WeatherPak connectors on the left are the headlight wiring connectors - I'll hook them up into the inline connectors once I have the main power lead hooked up tot he mega fuse. The connector for the washer pump is sitting right in front of the relays for now; I may adjust this with some creative reworking of the factory harness later. or now, it's fine.
Some folks may notice that the "always hot" side of the circuit breaker connections are very close to the unused battery tray here, and be concerned about shorts. It is close, but it's OK - the tray is plastic, so nothing can short out. Sometimes plastic parts are a good thing...
I finally broke out the real camera and took some decent pictures of things. Here's the relay and circuit breaker wiring.
The main power feed.
The wiring out to the driving lights.
The wiring out to the fog lights.
The wiring where it goes through the firewall. The second photo is a close-up of the grommet in the firewall - it's about dead center in the picture. I sized this so that you can remove the grommet plus wiring harness with connector inside the cab attached to it with undoing any of the wiring harness or cutting any wires - the grommet fits into a 1" hole in the firewall.
A quickie cell phone camera picture of the dash switches in their not-on states, before the switches were fully mounted. At this point the switches are just sitting in the rough openings in the dash.
Same thing, this time with a real camera and the switches all turned on (aka, in the "always on" position) and then in their normal/"automatic on" positions.
Grill Guard and Lighting Pictures
Here's a not-great cell phone picture of the grill guard with the driving lights mounted to it, before it was installed on the truck. You get the idea.
More not-so-great cell phone pictures of the grill guard w/ driving lights and the fog lights mounted to the front bumper. I can't wait to light all this up and have a directed supernova on my front bumper. In addition to being able to see better, it'll make high-beaming folks who drive too slow in the left lane a lot more fun. :-)
Here's the first test firing of the driving lights using some temporary wiring under the dash.
Same thing, after pulling the truck out of the garage to see what the beam patterns looked like. Very bright, but it definitely needs adjusting, wouldn't you say? :-) First photo is with a camera flash, second is without.
Same thing, after some basic adjustment. Better, but still not perfect, but enough for a first test drive.
The view from the front, on high beams with the driving lights on. First photo is with a camera flash, the second is without a flash. Note that the high beam and low beam headlights are both on - this is the diode that I added in the diagrams above. It makes a big difference in the high beam light pattern and overall visibility, even without the driving lights. Adding the driving lights takes the visibility from "pretty nice" to "wow". Bueno++.
With all these options, decoding the option list to sort out the details for servicing was important. So, I spent some time at the local dealer and sorted out almost all of the options on the glove box sticker. Yes, there really are this many. Wow. I guess since a Suburban could be ordered as a really "Plain Jane" stripped down model as a base, virtually everything is an "option". That means that a well equipped Suburban of this era got a pretty sizable option list...
This was vehicle #36. My most expensive "used vehicle" to date.
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Page last updated 07/19/2012 08:38:40 PM