1996 GMC K3500 DRW, Extended Cab, Flatbed, 454, NV-4500

[83GMCK2500]

As the title states:

1996 GMC Sierra Extended Cab 4x4 3500 Dual Rear Wheel - 196,### miles
Vortec 454
New Venture 4500 5-speed manual transmission
Borg Warner (something) floor shift transfer case (with this tcase and transmission combo the truck has 3 PTO provisions)
FACTORY 4.56 gears w/G80 in the rear
Chrome wheels that have been painted black
Dark Hunt Club Red Metallic exterior paint
Light smoke gray cloth interior, 60/40 split bench with lumbar on both sides.
One atrocious analog radio that wasn't even connected, the pigtail had been hacked off.

Pictures from the day we looked at it and brought it home. Year should be 2011 from the camera, forgot that it had been reset.

[83GMCK2500]

Oh, so my dad got this truck as he intends to buy a gooseneck large enough to haul either the D4-7U, JD 3020, or vibratory roller that he recently bought. He wanted the added tires of a dually to do so. This thing was priced right to allow him lots of room to customize it.

Initial plans: flatbed, upgraded seats, fix the dings and scrapes on the cab, polish the paint, fix any oil leaks. (My dad HATES it when vehicles mark their territory.)

My dad ran up to a junkyard in Spokane and picked up full power heated leather seats out of a 2000 Yukon Denali (the spiffy two-tone gray ones) and on his way back David (88GMCTruck) and I met him at a midway point and showed him David's 99 that he's been building. My dad instantly added Kodiak handles, towing mirrors and overhead console w/comp & temp to his list of goodies.

In case anyone is wondering it is consistently getting 12 MPG on the hwy, had it serviced and checked over, everything is spiffy. It's had the radiator replaced recently, new plugs and wires, etc.

[83GMCK2500]

*** This text written back in 2011***

Last Friday night, David (88GMCtruck, around the internet) and I dissected a GMT400 cross body harness. Instead of swapping the harnesses directly, we decided it would be easier to build a mirror harness (since it requires additional wires anyway) and just splice it in with the existing truck's harness. We also pre-built some additional harnesses for the overhead console, autodim mirror, compass/temp, and steering wheel audio controls. Here is the pictures of that sticky tape and wire mess.



After getting down to Dayton, we tore into the truck. An hour later David and I created this:




Installing the mirror harness




And the mirrors




Leftovers from the westcoasters. Does not want.



Getting the stereo plug wired up, as well as the audio controls and overhead compass/temp unit, and putting the dash back together.

[83GMCK2500]

***This text also continued from 2011.***

Installing the OH console



Pulled the seats, wired the truck for the power/heated Denali seats


Cleaning up a bit of underhood wiring




Grille & bumper removal. Wired in the temp sensor for the OH console, replaced the corner lights with OEM amber ones, and installed a new TD bumper.




How we left it last weekend.



Just as a summary, here is what David, my father and myself collectively accomplished this past weekend.

- Removed entire dash, door panels, seats and carpet for cleaning
- Wired in mirror harness (truck had west coast mirrors) with power/heated/clearance/signal mirrors. Use factory rear defrost HVAC controls for the heated mirrors
- Installed OH console with compass and temp computer
- Modified map lights to function as dome lights
- Wired in stereo plug (was missing) and installed Delco CD stereo
- Pre-wiring for autodim mirror
- Pre-wiring for steering wheel audio controls
- Pre-wiring for power heated seats
- Cleaned up PO's past wiring endeavors (lots of misc crap that was shoddily done)
- Fixed battery cables
- Fixed wiper washers
- Installed new diesel bumper
- Installed OEM amber corners


And in the upcoming weeks, we will be going back, once more parts are sourced and time allows. Here is the future plans.
- Wire in lighting for bradford flatbed
- Wire 7-way trailer plug
- 4-high headlights
- Fog lights in bumper
- Denali leather seats and grey pickup center console
- Kodiak door handles
- Stainless trim rings & GMC center caps.

[83GMCK2500]

***Text continued from 2011.***

While David was working in the truck I was underneath removing what I shall politely refer to as "cowboy wiring". The trailer harness was fubared beyond belief, those extra running lights on that scaffolding were hacked into the REAR DUALLY FENDER clearance lights. There was a pair of CB antenna mounts in the front corners of the bed with ~6' of coax still attached that I removed from underneath. The driver's side coax was pinched between the fuel tank and crossmember, had to lower the tank to extract it. Additionally the monkey that installed the antenna mounts knocked some BIG holes in the bed corners and then filled them in with great gobs of silicone.

I also pulled the batteries, pulled the trays, cleaned and painted the primary tray, cleaned and made the battery cables proper, ran the wire for the temp sensor, and lots of misc things.

[chevyboy73]

wow lots of work! looking good though! i know 88GMCTRUCK from gmt400!

[83GMCK2500]

Update:

- Steering wheel audio controls installed, after some *cough* minor troubleshooting they work great. Sooooo handy. Also, so much nicer to use a puller on steering wheel as opposed to brute force. After removing three (or four) by hand, I'm done with that crap.

- I've noticed that at low speeds if I need to stab the brakes (pedestrian/grandma/idiot/etc) the steering wheel pulls left. It brakes evenly from higher speeds. This weekend I started in the front and dug in. Wheels off, first observation: driver's side has uneven pad wear, ~ 1/8" difference in-out. Passenger side, also uneven, call it 3/16" in-out, noticeably more than other side, but not a great deal. Started on the DS, pried the caliper over a bit to compress the piston, pulled the pins, pried caliper off. Got a good look at the rotor, noticeable ridge on both in-out faces at edge, slight waviness when running fingers from inside diameter out. Pulled the pads off, they're a mid-grade semi metallic pad, other than uneven thickness they looked good, not worn unevenly by themselves and no cracks. Bolted the caliper back up, won't slide. Not even a little. Hmmmmmmmm. Was able to free up one of the slides, took a wire brush and a file to the faces of the bracket ears and the caliper edges and cleaned them up, but one slide remains seized. Fought it for quite a while, didn't have a c-clamp or anything to use as a press, unfortunately. Don't know how something can get so stuck in a rubber sleeve. Cleaned things up the best I could and lubed what was accessible. Onto the passenger side. Repeated same procedure, findings: rotor has a much heavier ridge on the outer radius, also, noticeably more distortion on the faces when running fingers from inside diameter out. Again, other than uneven thickness, pads were ok. Felt the sleeves on this side and they actually moved, stiffly, but they moved. Bolted the unloaded caliper up and even with mobile sleeves it drug hard. After much filing and brushing between bracket ears and caliper it slid decently. Lubed what I could and reassembled. Thinking on heading home to Dad's shop this next weekend and pressing that other sleeve out and cleaning it.

Summary brake observations: calipers, rotors, knuckle, bearing flanges, etc all have healthy level of rust/scale/grime on them. Given the environment this truck has been in I assume these parts have not been changed for quite some time. Given how much material is left on the pads +/- 5/16"-3/8" (relatively fresh) I assume the last brake job was to throw a set of pads on. I doubt the rotors were turned. The passenger side caliper had newer sleeves than the one I was able to remove from the driver's side. All of the slides that I was able to hold in my hands look to have been overtightened, the ends were slightly mushroomed. Never made it to the rear brakes, was raining and after messing with front and rotating all 6 tires/wheels I was soaked.

[83GMCK2500]

Lighting Upgrades!!!

A couple months or so ago I cleaned, lubricated, and installed a set of 88/89 dual sealed beam adjusters. I loaded the adjusters with the conversion lenses that LMC sells and 4,300K 35W HIDs. Utilizing a GM PDL relay (6-pin, two relays w/common pwr/gnd) and a diode I wired up a temporary relay switched 4-Hi harness.

HIDs in 88-89 adjusters.

[83GMCK2500]

Last weekend the less-than-temporary headlamp harness was created. With the help of my good friend we removed the OEM harnesses, dissected the BS headlight wiring, and re-created them using all 12-gauge wiring. During this time wiring for fog lights and driving lights were added. We used 4 heavy duty Bosch relays with weatherpack connectors to power the circuits, lowbeam, highbeam, driving and fog lights. The highbeam switch will trigger low, high and driving lights for a 6-hi combination. The fogs are independently switched. Everything is fully soldered and weatherproofed.



After dissection


All new gauge leads.


Wiring

Laying out relay sockets

Yellow leads on relays will be triggers, here is the highbeam trigger with diodes for triggering low & driving lights.

One of the completed relay socket sets, this one had orange trigger wires.




Relay mounting under the ECM


Completed harness



After adding the harness


***Disclaimer, some of these pictures were taken by me, the rest by my friend. This upgrade was simultaneously performed on two trucks, his and mine. The text above has been edited but the body of it are his words. (I'm being lazy and copying from his thread, elsewhere.)

[83GMCK2500]

After the headlamp harness upgrade I installed a new & upgraded alternator on my truck. (Unrelated to harness, it just happened to die the next day.)

I have the details on alternator upgrade in this thread: AD244 Alternator Upgrade for 96+ GMT-400s

[83GMCK2500]

Somewhere in here (2 weekends ago, yes my timeline is all out of whack), I took the time to hit the truck with some heavy cut, fine cut, then cleaner wax. The sides need some more work, but it sure beads water on the top.




Also, installed OEM LED cab light bulbs.

[Truck Guy99]

Nice truck! I love everything except the flatbed. I personally would have kept the dually bed but it's just personal preference. Keep up the great work!

[Tx Firefighter]

Are you going to try and find genuine Kodiak door handles or go with the aftermarket ones like I did ?

I ordered all of the rods and clips and pawls through my GM buddy and the door handles from Rockauto. I'd have to add it up, but it's somewhere in the neighborhood of 110 bucks for all of it total. My GM prices seem to be about 10 percent under GMpartdirect prices. And, I always have a Rockauto discount code if you or anyone else ever needs one.

[83GMCK2500]

Originally Posted by Tx Firefighter

Are you going to try and find genuine Kodiak door handles or go with the aftermarket ones like I did ?

I ordered all of the rods and clips and pawls through my GM buddy and the door handles from Rockauto. I'd have to add it up, but it's somewhere in the neighborhood of 110 bucks for all of it total. My GM prices seem to be about 10 percent under GMpartdirect prices. And, I always have a Rockauto discount code if you or anyone else ever needs one.

You have caught me with my thread well and truly out of date. Last winter my dad and I scrounged some local yards and picked up a set of handles with rods off of a 95+ 3500HD. They were chipped and weren't looking to hot, but go figure, they still worked great. Disassembled and dropped off at a local powder coater, we picked them up this spring and I installed them about a month ago.

Disassembled:


Coated:


The coating was pretty thick and I had to take a round file to the saddle that the paddle sits in, and the slot adjacent to it. In hindsight I should have masked off some areas on the handles, but not having any p-coating experience myself... :/

[Hankster]

I like the truck, y'all should find a tahoe limited front bumper for it.. (Still has the factory cooling cut-outs, no moldings, and its painted) .

[83GMCK2500]

Yeah, Z71 Tahoe, Tahoe Limited, & ...I think very base models w/diesel all had the paintable fronts with air holes. I do want one. I would gloss black it in a heartbeat. I've been thinking about one of the GMC grilles from 88-93 for it lately.

[Hankster]

I'd like to see the bumper.. on the grille, I think it would look good, but look even better, if it was a painted one.

[83GMCK2500]

Agreed. I think I'll be keeping my eyes open for a variety of front end parts. With the red truck body and black flatbed I want to minimize the chrome as much as possible. To me, that means swap out the aftermarket boards for Tahoe ones and either a body colored bumper or black bumper. I think a body colored bumper with a black Z71 grille guard would look pretty good or the other way around, black bumper and body colored guard. Really would only have chrome in the center of the grille, ideally.

The wheels are killing me as well. They are a mismatched set of chromed steel wheels that are peeling and just generally hideous. Alcoas or 19.5" steelies are at the top of the list. Ghah...

I finished my degree here a few months ago and have been looking for something near enough to my field that I can remain focused on and afford me the opportunity to tinker. I know better than to hold out for the "perfect job" and I am sending my resume out on anything I am remotely qualified for.

[Truck Guy99]

Any updates?

[83GMCK2500]

Update: nothing worthy of noting...yet. I do have a big update coming in the near future. Just maintaining it really:

• Installed more versatile trailer socket, upgraded brake controller, improved bed-chassis electrical connections.
• Replaced cruise control servo.
• Replaced oil pressure sensor.
• HVAC fan control switch & resistor.
• Wiper motor pulse board.

I was having a random short/feedback issue with my bed lighting and trailer lighting, I traced the problem to a hideous hack job of wiring from the people who installed the bed. There was a half-mile of electrical tape, some wire nuts, some more electrical tape, some zip ties and a portion of the pickup bed wiring used to connect the bed and trailer socket to the chassis. Ohhhh heeeeeeck no, that won't do. I spliced in the 7-pin Pollak connector that GM uses on the GMT-800 and newer trucks. Ref: Though I did not use butt connectors...soldering iron...lined heat shrink. I hate doing this kind of thing twice. I incorporated the 12V feed, brake controller, and reverse lights as is done on the newer trucks. The bed plugs into the chassis and on the bedside of the connection I have a secondary pigtail which plugs into the trailer socket. If the socket fails I can unplug it and replace it; if I need to pull the bed, it's one plug, one ground strap and the fuel neck. The new (to me) brake controller is a Tekonsha Prodigy, and the new socket:

At first my cruise control servo was kicking out when I went over a large enough bump, the kicking out evolved into a really obnoxious surging of the throttle at times. The servo is the same for many many different GM vehicles, it isn't 454 specific or GMT-400 platform specific. The part that IS specific to my truck and engine is the cable, thankfully it takes 30-45 seconds to swap the cables.

Ughhh, the oil pressure sending unit. The devil incarnate. I moved my truck a very short distance and noticed a couple drips of oil on the ground. Not good, everything has been replaced recently: lines, cover seal, main seal, pan gasket, ev-er-y-thing. The truck does not leak. So when it leaked, I started looking. It honestly took a while to find, the leak got pretty bad. It appears that internally the oil pressure sending unit failed and allowed oil to leak through the body of it. I had oil pumping out the weatherpack connector at the top of it, running down the sensor, to the top of the block, and diverting down two different ribs of the bellhousing and finally onto the exhaust crossover. Viewed with truck running, laying across the engine with mirror and flashlight. There is a specialized 1-1/16" socket with very thin walls designed for these sending units. Get one. The sensor to block clearance at the back of the valley requires it. I ended up snapping the plastic portion of the old sending unit off and unscrewing the base with a ground down standard socket. Install went very smoothly with the proper socket.

To Be Continued...

[chevyboy73]

very nice looking job, you and david do excellent jobs on very detailed stuff. do you or him happen to have a diagram on how you did the head light harness? something i'm very interested in doing.

[Palf70Step]

Lots of nice details, thanks for the photos and descriptions. Love the look of you truck!

[83GMCK2500]

Well, sh!t happens. Flatbed down.

[83GMCK2500]

I rearended an F550 w/contractor bed, I was just coming down from 60, he might have been going 25 when he just cut into my lane with no signal or anything. He was cited for improper lane change, a friend towed me home.

I had a 2015 Tahoe LTZ rental, it heated my ass in the mornings and cooled it in the afternoons, it was marvelous.

Insurance company totaled the truck. Frame is straight, I hit the liftgate on the F550 outside my rail. It needed bumper, brackets, passenger fender, inner fender, battery, battery tray, hood, core support, grille, lights, aux fan, condenser, radiator, fan shroud, engine fan, fan clutch, water pump.

I fought them for a week on a value. I told them to find me a 4x4 3500 dually, big block, manual transmission truck, make it equivalent. After 2-3 days they called me and asked me if they could increase their radius out beyond 150 miles. I told them that I searched out 1,500 miles to find a 4x4 2500, big block, manual transmission truck, be my guest. They finally came back with a 2wd 3500 dually, 350, auto with additions for 4x4, engine, and trans when it was all over

Needless to say, I bought the damned thing back from them.

[83GMCK2500]

Here's some of the carnage, I dug into it after a few days too see what all it needed.


Yeah, it wasn't even off the trailer yet.