[davester3500]

Finished mounting all the light boxes. Cut out the end of the horizontal boxes, for the side clearance light.

Naturally, after making the holes (the front boxes came with holes), I realize I bought 2" lights and the holes are sized for 2 1/2" lights, so tomorrow it's back to the store for more lights. At least I can use these to fix the couple of busted lights on my trailer...

After printing out the wiring diagrams and connector pins for the tail and clearance lights, started on the wiring for one of the taillight boxes, got stuck on coming up with a good way to join a bunch of wires of varying gauges together. Moved on the the backup light, wired it, tried it out, it didn't work, so decided to call it a day. Later on, I was looking at the wiring diagrams some more, and realized the ground for the taillights is disconnected, as it's also used as the ground for the fuel filler port...

 

[RedSLEd]

Any guesses on how much the flatbed itself weighs? Looks pretty stout.

 

[davester3500]

It's similar to the one that's on my '04 3500, which is a cab & chassis, and already had a wood flatbed on it.
From working out the weight per foot of the main steel parts and how much is in there, it'll be somewhere around 500lbs with the wood planks and underbed box.

 

[davester3500]

Made a pair of wiring harnesses for the rear lights, had go get some resistors and some more yellow wire to color code the wires. This is much better than the previous, similar harness I made for my other truck (also replace the oem lights w a custom setup).

With the previous harness, I left the pigtails at full length, and only ran wire of whatever color I had on hand, to make it work, and then just had a jumble of wires in the housing, that I have to re-figure out every time it gets disassembled (which, fortunately, rarely needs to be done).

For this harness, I cut the pigtails fairly short, then color coded wires (same as the oem colors, mostly), in loom, to the plugs going into the oem harness that then plugs in the rear junction box, so when it comes apart in the future, it's just plugging the same color wires together and done. First harness took quite a while to do, second went much faster, as I could just copy the first. Tested them and they work great.

Tomorrow, I'll make the harness's going to the front lights, with some repinning of the oem setup (the original clearance/license plate harness was ripped apart, so I swapped on the harness from the parts truck onto it). Then it's installing the harness and lights and welding on tabs to the bed for securing the harness.

 

[davester3500]

Made good progress today.

First, completed the harnesses for the front clearance lights, and adding pins to the right plug going into the rear junction box to match the oem setup. Tested, and they both worked fine, so then I drilled a 5/8" hole in all the light housings for a grommet to pass the wires through, made and welded on a bunch of tabs for fastening the harnesses in place, and installed all the lights
Rear harness to taillights:

Front harnesses to clearance lights (clean black loom running along the frame rail/board, then splits at the front crossmember):

Taillights (matches oem setup, red lights are park/stop/turn lights, center is backup). There's also a red, round clearance light mounted in the end of the housing, not visible in the pic).

Front clearance light:

Mounted the mudflaps and anti-sail brackets:

Need to straighten the exhaust, so it doesn't melt the mudflap:

Got the fuel filler port modified to work. Had to straighten the tube, then insert extensions in both the filler tube and the ground wire. I'm considering modifying the mount for the fill port, as with the cap on, it sticks out more than what I would like. It looked fine w/o the filler cap on when I was making it, I should have checked with the filler cap.

Tomorrow, it's just some final tasks:
-make a mount for the evap tank vent
-modify the exhaust
-buy & install the wood planks
-fix some cross-threaded nuts on the bumper's mounting bracket

 

[davester3500]

Getting so close.

After cutting/grinding off the old welded on crossthreaded nuts from the bumper mount, welding on new nuts, and then reinstalling, I moved on to fixing the exhaust.

If you look at my last post, the exhaust was pointing right at one of the mudflaps, and would quickly melt/burn it if left that way. I cut out the last outward bend in the exhaust, bent it straight, and then welded the seam together:

After driving it around later in the day, the fix works, in that the end hasn't fallen off, and the mudflap shows no signs of heat damage.

Made a simple bracket for the evap vent to snap into. Used an angle grinder w cutoff wheel to cut the two slots just the right distance apart in a 1x1/8" strip of steel, welded another strip to it to close off the holes, then welded it to the crossmember. The vent has two hook-style clips that snap into place to hold it.

On the shopping trip to pick up the wood for the deck:

I have considered moving the bumper back, by welding on some extensions to the frame (basically cutting the end of the frame off my parts truck, and welding it onto this one, but that would make using the hitch much more difficult to use, and I'm not comfortable with modifying the hitch and/or it's mounting points to move it back.

Tomorrow, it's cutting up the lumber I bought and then bolting it down to finish off this part of the project.

 

[davester3500]

Wood deck installed:

Woodworking is not my forte, so the stake pocket cutouts aren't great, but overall it turned out well.

 

[nealinator]

You are making fast progress with that Dave!

 

[davester3500]

I had noticed the doors on the driver's side of the truck weren't lined up great, so I took some time to adjust first the rear door, then the striker and that made the front look ok. As part of doing this, I also noticed that the roof rain gutter seal was missing on that side of the truck, and then that there was a line of holes for mounting something on the roof (also on the other side of the truck, under the seal). So, after carefully removing the seal from the parts truck w/o damaging the clips too much, I also fixed the holes by:
-using a rounded off rod to push in the holes a bit (as they were used for metal screws, which pulled the edges outwards)
-flap wheeled the area to bare steel

-soldered the holes closed
-flap wheeled it flat (so no solder was proud of the surrounding steel)

-thin coat of bondo to make it flat

Repeated on the other side.
I left it like this, as I don't have paint for it. Once I get some (doesn't have to be color matched, as this isn't visible), I'll sand it smooth and then paint.
Installed the gutter seal to finish this for today.

Decided to work on the main remaining issue with using it as a work truck, that the trailer brake controller wasn't working. There was several codes U2099 and C1112 for it. I had previously found a busted wire for one of the trailer lights, so I started w testing that there was a good wire between the TBC relay, TBC computer and the trailer connector, and there was, but using my Autel PS100, it seemed as if there was also a short to ground for that wire. So, after unwrapping the harness and examining it, there was no short to ground. It turns out the PS100 will incorrectly generate a 0 ohm reading if the probe is touched to ground, regardless of what the other lead is connected to.

So, with the harness unwrapped, I plugged in the connectors to the relay and computer, then hooked up a headlight bulb to the trailer connector, turned on the ignition and somewhat surprisingly, it flashed on briefly, but then the IP didn't report a problem (which it normally does report "Service Trailer Brake System"). And the manual slider turned the bulb on, as well as pressing the brake pedal, so it seems to be working.

I guess the problem likely is with the big connector going to the trailer brake controller computer, the connection retention mechanism seems to be partially broken, so I have to figure out how to depin it to swap over the connector from the parts truck.

 

[davester3500]

Success! I googled in the past for trying to figure out how to depin the 47 pin connector to the ITBC computer with no luck, but I guess I used slightly different terms and found a youtube video specifically on how the connector latches as well as depinning it.

Replacement Connectors

We offer replacement 47 way, sealed female connectors. these connectors are compatible with the following modules, found in 2007 and newer gm trucks/suvs: Fuel System Control, INTEGRATED trailer br…

gmflash.com

After watching it, I re-examined the connector on my truck, and it didn't seem broken, the lever properly moved the part that grabs the posts on each side of the connector and pulls it together. I did notice the silicon seal was poking out one side, so pulled off the pin retainer, then pulled out the seal. Tried the connector this way, and it engaged and locked on fine. Reinstalled the silicon seal, and pin retainer, tried again, no go. Removed the pin retainer, leaving the seal, and still no go. Removed the seal, lubed it up with some dielectric grease, reassembled w pin retainer, and like magic, it slide together just fine. Retested w the light bulb, worked fine, so I re-loomed everything w new loom, retested again, still worked, so it's done.

This doesn't show much, other than the connector. The white is the pin retainer, behind it is the silicon seal that was somehow catching on the lip of the connector on the ITBC housing, preventing the connector from being pulled on all the way.

 

[davester3500]

After work, I got to swapping over the front clip from the parts truck, as the fenders and hood are in better condition than the ones on the truck. They aren't perfect, but they are a lot less dented and scratched. It's not done yet, still need to get the hood on and grille.

Parts truck today. I'll install the bad parts on it, just so it doesn't look quite as bad in the yard.

Didn't take any progress pics, it's just a lot of unbolting and then bolting back on. Notably, the original felt padding between the fender and cab had come loose, got scrunched up and looked terrible, both hanging out the corner of the fender and inside the door jam. The parts truck pieces were a little nicer, so I used them, but first banged out most of the dirt (didn't think of vacuuming it until afterwards), which both got most of the dirt off the outside of them, and also restored their flexibility. Then some 3M double-sided tape (for external body trim, but it's all I had here) and it looked much better.

This work did come at some cost, I cut the windshield wiper hose while removing the hood, and a 10mm deep socket has disappeared somewhere in the front end.

I should have it done tomorrow, and will post pics of the completed job then.

 

[Bradley21sanders]

Should take a torch to those wood boards really good then seal it!

 

[davester3500]

Got the hood back on w/o damaging/scratching anything too much, then the headlights, grille, wheel well liners, and then the hood liner (the parts truck hood didn't have the liner, this truck did, so swapped it to the new hood).

Then removed the air inlet grille and replaced the washer fluid tube from the parts truck. Would have just swapped over the whole air grille, but the parts truck one was broken in one corner. What made the job annoying was that the FSM doesn't note/indicate there is a push-pin in the center of it, and there is a gap between the plastic grille and the metal spot the pin goes into, so it was difficult to get leverage on the pin to pull it out w/o damaging the grille.

With the grilles off, removing the hose fittings was annoying until I remembered to use this tool to push in the side retaining clips while pulling out the fitting from behind.

Reinstalled everything, w new wiper blades. And, this time I remembered to remove the plastic covering from the blade itself.

Finally, some pics of the completed work. The truck looks a million times better than it did way back when I bought it:

Work is going to pic up now, so not a lot more work will be done to it soon. I'll swap the bumper top cover, as this one is cracked and the chrome is peeling everywhere, I need to find new fog light housings and then wire them up, and I want to swap the rear doors, or at least the windows w the parts truck as they tinted, just to make it a little harder to check out the stuff I will store in the back row.

 

[shakenfake]

Awesome dave. Good job.

 

[davester3500]

Fixed up some minor bits, still need to install them on the truck.

First, the inlet to the air filter housing has a replaceable piece with foam stuck to it, to kind of seal against the fender. The part from the truck was broken and all the foam was worn off, while the part from the parts truck just had the foam worn off. New part is $40+, decided to by some foam weatherstripping and apply it, to see how it works out:

Next up, the idler and tensioner pulleys. On both trucks & both parts, the bearings were making noise, and replacements are $30+ each. Decided to try replacing the bearings. The bearing in the idler is easy to replace, it just presses in/out. The bearing in the tensioner pulley is a bit more sketchy, in that both sides of the outer race of the bearing are covered with plastic. I clumsily used an angle grinder to remove the edge covering the bearing (and some other spots), and then pressed the old bearing out/new bearing in. I'll install them soon and see how they run. Both use a 6203 sealed bearing.

 

[davester3500]

Fixed up the radiator cover from the parts truck, to install in the main truck. IDK why/how but both of them are cracked, the original one has a number of cracks and missing a piece, the parts truck just one long crack on one side. I guess it was just too much trouble to pull all the pins out, so you just yank on it...

Anyway, I have a plastic welding kit with a bunch of different type welding rods to go with it. From examining the part, I found "PP" imprinted in it, so I went with it being made out of Polypropylene, and used that type of filler rod to weld up the crack.

This is the kit I have. It's a gas-iron with several different tips, and came with a couple different types of rods, and I have since bought some other types, for repairing different types of plastic (https://www.princessauto.com/en/plastic-welding-kit/product/PA0008699134). It works well, the instructions suck, and when I first got it, it took me awhile to figure out how to get the iron lit and then stay on. Fortunately, I then wrote my own instructions on how to do it, so I could get it going right away.

Fixed cover. Didn't need to use a lot of filler, mainly just where there is a moulded in crease in the plastic.

Pro tip: Do not use your finger to test if the plastic has cooled.

 

[Bradley21sanders]

Otherwise permanent finger print?

 

[davester3500]

Otherwise permanent finger print?

More that the hot plastic comes off and sticks to your skin, burning it for a longer time

 

[davester3500]

I've been driving the truck occasionally (my '04 3500 is my DD), and it's generally been working ok. I made some ramps to mount on the flatbed, to make loading/unloading equipment on it easier and safer, and those have been working well.

Only problem (until today) that's turned up is a code indicating one of the cat's isn't up to snuff. I'll try swapping the sensor w one from the parts truck, but I don't expect that to fix the problem. I'll cut the cat out and replace it w one from the original pair from the truck, these are from the parts truck, as the pipe wasn't all dented up.

Today's problem likely will be annoying/hard to find. I was driving on a local highway to a worksite, and suddenly all the gauges went to zero (except for the voltage gauge, which stayed just below straight up). Engine still was running fine, and I could speed up/slow down. Fired up Torque on the radio, it connected and speed/rpm gauges worked there. Then, when I exitted the hwy and hit a stop light, once it turned green, the truck wouldn't shift out of first. I limped to the worksite, which wasn't too far, and 1st was all it would do. Reverse didn't work (behaved like neutral, just rolled down a driveway when I used it), just P, N and 1st. Worked for a couple hours, then fired up the truck, and everything worked as normal (gauges all worked, transmission worked fine), it was like nothing ever happened.

 

[davester3500]

Finally made some time and got started w installing the backup camera. Today was figuring out how the Eonon q80pro system worked, and then how to alter it to work how I want.

Installing it as Eonon indicates would work fine, and is pretty simple (so it automatically turns on the backup camera when you shift into reverse, and then back to the normal screen view when you shift out of reverse), but I wanted the ability to manually turn the camera on/off as well.

Googled for finding a reverse signal for a gmt900, which came up w this post: Reverse wire for backup camera.
which is exactly right. And I got one of the connectors and some pins from my parts truck, so it's a solid, non-skanky connection to both the reverse and power pins. One thing to note, the truck needs to be running to get the reverse signal (which is IIRC is different from my '04 sierra, which does signal it's in reverse even w the engine not running).

Then removed the Q80Pro HU, hooked up the camera and some test leads to send powe and ground to the camera, and tested to make sure the setup worked (which took awhile to figure out how to turn the backup camera back on through the HU settings UI). I also determined that the power wire for the camera can be connected either at the camera end (where the ground wire also terminates), or by the connector to HU (which I'll use, so the camera and HU get power at the same time).

With the camera working, I determined that the HU shifts into backup mode independently of whether the camera is powered or not (or provides a signal), then started back-probing connectors to find which pin to the HU is the reverse signal, which turned out to be the brown wire on connector A to the HU. Cutting and stripping that wire, then applying power to it (and the camera) confirumed that it would switch to backup mode when power was applied to it.

I hard-wired the HU and camera to the backup signal in the MBEC, w some extra wire so I can redo it later when I get a SPDT ON-ON switch, and ran the camera cable up beside the HVAC system, so I don't have to tear apart the dash again. Hopefully, I'll have time tomorrow after work to pull the front passenger seat out, pull up the floor mat, remove the plug in the floor (the P.O. had a 2" hole underneath the seat for something, I made a plug for it), string and mount the camera to the back and wire up the ground wire. WIth that, the setup will work as originally intended, until I had source a rocker switch to make it work like I want.