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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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Been driving the truck almost exclusively on my home brew fuel. Especially since diesel is $6 a gallon here now lol.

Been running great. Mixed up a new batch last night. Did 2 gallons of oil to 3 gallons diesel/gas mix.
My home brew fuel is likely done for the year. Went out last night and filled up with diesel. The cold Temps are here so the oil mix will thicken up too much to make it worth running. I could still add a little bit, but I'll likely just run diesel through the winter to play it safe.

I'm also planning on ordering a new turbo for the truck. I debated rebuilding the one I have torn down, but I think I'll just go with a new one, and may go with an hx35 or hx40 instead.
The 6.2s are a higher compression ratio than the 6.5s that had a turbo on them. The 6.2 is a 22:1 while the turbo 6.5 motors were a 16:1. So the 6.2s can't handle as much boost, at around 10-12psi at the absolute most and still be sort of safe.

But the 6.5s in stock form are really only a 15-18psi motor safely.

They definitely don't like to be pushed too much, but the 6.2 motors actually had the better bottom end compared to some of the 6.5s.

I'd likely only run 6-8 psi max. Maybe 10psi depending on what my EGTs look like. But that's also sorta my dilemma with the turbo choice. The HX35 isn't the best at the lower boost levels, but it flows much better and will allow cooler IAT and EGT numbers. But thr GM turbos are designed to work better at the lower boost levels, but are fairly restrictive, which means higher IAT and EGT
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The 6.2 with the turbo is fun to drive for what it is. Buddy of mine has one with a banks kit on it, I remember being mildly impressed driving it around.

Sent from my iPhone using Tapatalk
Yeah from what they are N/A, a little boost definitely wakes them up.

I'm looking forward to it. Definitely still not very impressive from today's standards, but as long as it's kept in mind what they are, they are neat.
Ordered my beacon light today for plowing. Went with a 29" amber/white bar. Should be decent. Nothing fancy since I'm not doing it professionally or anything. I just wanted something to be seen and probably still ignored by the public lol.

Should be here later this week, I'll post pics when it arrives. Not sure if I will be able to install it or not this weekend. Foot is still sorta painful to do much on lol
Got my light today. It's freaking bright lol. Once I get it installed I'll take some videos of it
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Hoping to get time this weekend if weather permits to install the light bar. I got a different switch for it since I don't like the cigarette lighter plug style switch it came with.

I also devised some future plans for the truck, that are subject to change lol. But either way I'm sticking with the turbo setup. Then down the road a 4l80 swap. But I have also added a lift and some hmmwv 37s to the list. One thing that is making me bounce back and forth with that size lift is the plow. I'd like to retain the ability to plow with the truck. And a 6" lift is getting up there to be practical to plow with lol. So it could change to a more mild lift on 33s or 35s.
So I worked on the light bar today after work. I was not happy with my original plan. The height and size of the body means I have to mount the bar on the body itself rather than the top of the cab, which I knew.

But the thing I wasn't thinking of was that you can't really see it from the rear. So, I ordered a second bar. I did some testing with the bar I have, and what I think I'll do is take the bar apart and use it on either side of the top edge of the body in the rear. And then mount the other bar on the top of the cab. I'll wire them together so they will both come on the same time and the pattern change will work the same for both.
So I came across a bed on marketplace tonight. It's about an hour and a half away from me. It has a little rust on the one lower fender lip. But the rest is fairly clean. Came off a cucv, so it's camo. It'll get repainted anyway, buy the seller is throwing in a tailgate as well. Comes with tail lights too.

It'll take a little work to get it perfect, but for the price, it's about as clean as I'll find for PA without paying over a grand. Going to pick it up Saturday night.
Sweet! I was wondering which way you'd eventually go, full on bed or flat bed
Well I was open to either one, just depended on the cost of which I could obtain either one. I figured to build my own flat bed, with steel prices how they are, it would be over $1k beyond the time I got lights and all, plus the diamond plate isn't cheap at all. And then bed liner for it.

In paying $400 for the bed, and by the the time I paint it, and repair the one spot that's rusted, I'll be in it around $600 on the high end. So not too bad
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Also a fun fact for anyone who may be interested, technically once I put the bed on it, it will no longer be a M1031, but rather it will now be a M1028A1.

The M1028A1 trucks were the ones that were M1031 trucks that the military removed the SECM body off of and put a standard pickup bed on. These trucks differ from the M1008 trucks in that they retain the NP205 transfer case, as well as the limited slip diff up front. So while the M1008 and M1028 may look the same, they are different.

The M1031 was a chassis cab as purchased from GM. They either got the SECM body put on along with the PTO and generator, or the ones that were "leftover" and never got the SECM body installed were fitted with beds and labeled M1028.
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Awesome project. I've always loved the CUCV trucks & blazers.
Just got home with the bed. It's in the exact condition as described. Guy was a really cool dude, and great to deal with. Very straight forward guy and very fair deal.

If anyone need any driveline parts, for any GM truck, especially the square body trucks, give him a call or visit. Highy recommend him. Here's a link to his website. Hillbilly Wizard Home Page

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So I got my parts list together for the bed.

I'll need the bed side hinges, the support bars (or the cables if I decide to convert it), one latch for the tailgate, and the carriage bolts to secure the bed to the frame.

The parts listed are the stuff that was missing off the bed/tailgate. I found a complete kit that comes with everything including a new handle and all for around $120. So I may opt to do that instead of buying it piece by piece.

I will also need new sockets and wiring for the taillights. The one side is there, but corroded. The other side is missing. I also want to sand and polish, then clear the lenses. They are OEM lenses and in good shape other than being faded.

Last part that I may need, which I won't know until I put the bed on, is the filler neck. Luckily the bed came off a CUCV so the filler neck hole is the correct size. I just don't know if the length of the one that's on truck now will reach or not.
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Got my bed mounting hardware in today. Went with some 1/2-13, 316 stainless carriage bolts with 316 washers and nylock nuts.

They are longer than I needed at 5.5" but that won't be an issue. If it is, I'll just trim them down.
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Good ole mcmaster-carr, hopefully you were able to use a work discount lol

Neat info on the models as well
I was able to get them through work. I split my last vacation day for the year up so I'll have the next 2 weekends off. I plan on doing some work to the bed Saturday and then hopefully installing it next weekend.
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