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19trax95's 1986 CUCV M1028A1

16060 Views 358 Replies 24 Participants Last post by  19trax95
So I have been looking for a decent square body for some time now. Didn't really have my eyes on anything in particular, but the frame and body needed to be in as good of shape as I could find.

Last week I came across this beast on marketplace up in Massachusetts. It's a 1986 Chevy M1031. Which is the military CUCV service truck.

It is I'm great shape. Frame is rock solid, and the cab has very, very little rust. It is also mechanically sound. A couple little leaks, but that's to be expected.

It has the 6.2 diesel, th400 trans, np205 t case, king pin Dana 60 front axle with a limited slip, 14 BFF rear with locker, and 4.56 gears. The service body is all aluminum. It used to have a PTO driven generator and air compressor, but those have since been removed. The PTO is still on the t case though.

My plans are to keep it fairly original, but add a few creature comforts to suit me better.
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Got a fair bit of work done today. Now as much as I wanted, but still made decent headway.

I got the glow plugs replaced, new terminals installed on all 8 glow plug wires, tidied up the harnesses a little, ran wiring for my new fuse box, ran the wires for the relay to control said fuse box, cleaned up the radio wiring, and tested my tachometer.

To my surprise, all the old glow plugs came right out without any issues. By the looks of them, I would say they were original to the motor. I applied a little bit of copper antiseize to the new ones. I then installed all new weather sealed terminals for the glow plugs since the original ones were corroded, and half of them broke off with the spade part of the glow plug still in them. And the new plugs are the civilian Delco 60G plugs which have the typical 1/4" spade vs the military 13G delcos which have a narrower spade.

For my fuse box, which isn't quite done yet, I ran my heavy power and ground wires from the battery and chassis ground to the relay. I just need to run one more wire for the relay trip and put it to an ignition hot source. That way I can have my radio, light bars, fuel pump, etc all come on, or be able to come on, with the ignition only, and have their own dedicated fused circuit.

I like these little marine fuse panels since they are compact, and have a power bus bar, and a ground bus bar. Makes it really nice to wire stuff up. I have the larger version on my 15.

Here's a couple pics of the glow plugs. I'll grab some pics of the tach and fuse box once those are done.
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Truck project is finally almost done. I got the rest of the wiring wrapped up today, got the tach installed, fuse box mounted, new auxiliary switch plate made and installed, and the new alternator arrived and I got that installed.

Now my radio comes on with the key, and my light bar and beacon light is wired to the new ignition hot fuse box as well. The two switches on the new plate I made are for the light bar and beacon light.

I didn't realize how crappy the pics were until I went to upload them lol. I also greased the u joints, front end, and transfer case linkage.

I also may need to adjust the tach slightly. I feel like I may had set it a hair high. But I have no way of knowing exactly what the engine is running at, so I only set it off of what I assume the idle is based on the spec, and sound. Spec is 650-700, so I set it right around 650. I'll see what it's like driving it around and maybe make some adjustments.
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Its getting there for sure. It's been my daily for the past couple weeks. Come spring is when the real changes will start to happen.

I'm just glad to finally have the wiring straight and now it'll be so much easier to add things as needed.
Update- so the truck starts phenomenally now with the new glow plugs.

Before I'd have to cycle them twice, and give a little throttle input to get it to start quicker in the cold.

This morning I cycled them once, hit the key, no throttle, and it was running basically instantly. Definitely was much needed lol.
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New mufflers acquired. Just got the cheapest that advance auto had to offer lol. I had speed perks plus their sale so I got both for $52 after tax. It'll be better than the blown out rusted ones I have.

I didn't want anything crazy since come spring they will be coming off anyway in favor for a nice straight pipe from the turbo back.
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I’ve been following along with the project and enjoying it. I was on the engineering team responsible for development, production, and design maintenance of the FMTV’s. Also worked on development of MRAPS and other vehicles during Desert Storm, etc. Brings back memories. Our paint schemes were camo and desert tan CARC paint. I like the solid green look though on yours.

Regarding the recent glow plug install, I have always used a bit of the silver colored anti-seeze when doing plugs to help them not corrode, but when removing themfrom the truck recently after a bit over 100k, the anti-seeze seemed to be gummy and actually made it harder to remove them. Would the copper be better for this?
In my experience, I have stopped using the silver antiseize all together. I now only use copper or nickel.

I've found it holds up far better long term. It remains thinner. The silver I had was rated to 1200⁰ but I found it definitely broke down and got gummy like you found at higher heat areas like cylinder heads.

I use the copper on exhaust manifold bolts for the big bore diesel engines and have yet to have any issues with it becoming thick and gummy. And those can see sustained 1000⁰+ exhaust Temps for a long period of time during use and regen.
So I got the new mufflers on the truck last night. I thought the clamps would be good yet, but they aren't. They work, but don't seal the best. So if it stops raining today I'll throw some new ones on there.

But even with the small leak from the clamp, I really like the new mufflers. They actually sound way better than I thought they would.

They are quieter by miles than the blown out old ones lol. I can actually hear the motor and tires now lol.

So I can now say, the toyo MTs do have some noise. Not bad at all for how aggressive they are, but definitely noticeable compared to the ATs (obviously). But now I can cruise at 55mph nice and quiet (for a 6.2 lol).

Once I get the new clamps on and get the old tips out of the mufflers, I'll post a video. But I'm impressed for under $60 for the pair of them. No more clapped out sounding truck haha. Here's a picture of the old ones for example lol. As you can see, they were beyond shot.
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Definitely time to replace them hahah.
Nah, you can get muffler tape, couple wraps and it's good to go...
My new (well new used) filler neck arrived today thanks to John at hillbilly wizard.

I messaged him and he found one, made a page on his website, and shipped it out to me for an outstanding price. About a third of what I see the rest going for.

He even cleaned it up so it's nice shiny steel. I'm going to paint it tomorrow before I put it on the truck.
Fuel fill neck is painted. I planned on installing it today, but ran out of daylight.

I had too much other stuff to get done today. I did manage to get the oil changed. I made a gigantic mess lol. I ran the engine to get the oil warm, and the way the exhaust runs on these motors is right near the oil filter. I took the filter loose and then burned my arm on the exhaust and dropped the filter, which proceeded to land on the exhaust, upside down naturally, and run all over the place lol.

But nothing some brake clean didn't fix haha.

Tomorrow I'll get the fill neck installed and I also have a bed toolbox my buddy has that he doesn't want anymore so I'll probably go over and grab that.
Pretty much back to normal. I have a bump where it initially was crushed, but where the break was is fine. If I bend my toes a lot one way or the other it has mild discomfort but no pain. I got feeling back on the bottom of my foot as well. It seems the bump is getting smaller as time goes on.

But besides that, I've been back to normal work and all that. Walking is fine too. Definitely got lucky I think. Could have definitely been way worse had it not landed where it did.
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Got some more done today. Got the old mechanical fuel pump off the motor, and the new blockoff installed. Removing the old pump was the hardest part. The one line wouldn't come off so I had to cut it. Doesn't matter since it's dormant anyway and will be removed when I do the turbo swap. Then the top rear bolt was a pain to get at.

The rest was easy. I installed the new fuel fill neck. I had to shorten the hose on the tank end about 1" to get the hose to sit right and not have a partial kink in it. Then I bolted in the support plate and fill neck along with the vent hose. Filled the tank and it filled great.

Then I cut up parts of my old stock exhaust off my 17 to use the pipe for some tips to shoot the exhaust downward and away from the axle/brake lines. Actually sounds better now that it's not echoing under the bed.

I'm debating rigging up two tail pipes to make it actually exit the underside of the truck. I want to see what kind of scrap sections I can find at work.

And finally, I went and got some 1/2" pex pipe. I removed the door strikers and pressed the pex over the striker where the latch sits. Now my doors close really nicely with far less effort. Still need a firm close, but now they close first time, everything without needing to slam them. Definitely worth the $1 the pex costed me lol.
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As of now lift setup will be a 4" skyjacker, ORD zero rates to push the axle front 1", black max shocks all around, potentially remove some leafs in the rear and add a block to bring the rear to height as needed, and then HMMWV 37s on 24 bolt HMMWV wheels.

All subject to change until I actually order it lol.
Torque-y diesel and 4.56s should pair nice with 37s. Why those type of wheels though?
Eh I'll definitely notice a power loss. I'm only working with 150hp when it was brand new lol. And then it goes through the power sucking turbo 400 trans. But the turbo swap will definitely help.

But the wheels are to stick with the military theme. Plus they are cool looking. They will likely have the run flat inserts in them still, which I may remove in favor of a pvc bead lock. That will allow me to air down to the single digits without fear of blowing a bead. The hmmwv wheels are a single bead lock but the inserts press the outer bead into the inner and basically make it so you can't pop a bead at very low pressures.

At this time, I'm leaning towards the BFG Baja variety of hmmwv tires. The original goodyear MTs, while the cheapest of the three types (well technically 4) are not great in the snow, and are known to be very hard rubber as well as very loud.

The second option is the Goodyear MTR. These are better in the snow and quieter, as well as a softer overall ride. However, they are also known for some of them to experience sidewall cracking and sidewall blowouts. Military actually has a bulletin on it.

And lastly the BFG baja. These seem to be a middle ground of ok in snow, ok in mud, great on dirt and sand (obviously) and are a softer compound. I can currently get four 24 bolt wheels, with BFG tires on them, for just under $600 and they have 75% tread or better. No shipping needed since I can pick them up about an hour or so away.

Once I have the wheels, tires can be had much cheaper if I wanted to switch. Only downside is I'd need to stick with milsurp tires, or spend $1400 on a set of intercos since they are the only ones that still make tires for 16.5" wheels.
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Just swapped back to incandescent dash bulbs. The cheapy leds I put in got annoying. They were nice and bright, but they would flicker or go out at times. Oddly enough the speedometer bulbs never flickered or went out at all, but the fuel gauge and gear indicator bulbs would go out at random.

I'll order some better ones in the future but for now, back to the incandescent bulbs.

Also mounted the reverse led pods back up. Was able to use existing holes in the bumper. They aren't as tucked up and hidden as I like, but it works.
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