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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 my rear speakers mounted in the rear corners. I thought I had some stainless sheet metal at home but I guess not. So I'll need to make actual mounts for them. I also got my sub installed behind the seat.

Everything sounds really good. Still need to clean up the wiring once I finalize the position of everything.

I'll also be mixing my fuel today. Starting off with 5 gallons at a 70/30 mix of fuel to oil. I'll see how it likes it so in case it doesn't, it's only 5 gallons I need to drain out of the tank lol.
Awesome rig that will definitely turn some heads 😎👍
So the truck is officially running on used oil and the fuel mix.

I only mixed up around 4 gallons for now. My tank was basically on E, so it's mostly the new fuel in there.

I did change my mixture though. I went mostly used oil and then only used the fuel mix to dilute the oil so it was a little thinner.

Truck seems to run about the same as before, if not a touch smoother actually. I do have a very slight blue smoke from the exhaust. I only noticed it because I looked under the truck to grab a funnel I dropped and I saw the little bit of haze.

I will run this batch for a day or so to see how it does, and if everything is still good, I'll do half a tank of it
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Scored a set of mirrors off a guy I work with. They need to be cleaned up and painted, but I was going to paint them either way.

I'm hoping to get them sanded down and primed tonight. I need to get some more of the black paint that was used for the wheels and bumpers. Hopefully I can match it decently enough. I have the old can of what the guy used, so I should be able to get the same color.

I'll post some pics before and after I get them cleaned up.
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Wonder if someone riding behind you is like damn this guy is burning some oil he better get it checked...... Little do they know you are running off of it LOL
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It actually really doesn't smoke much. You can see a very slight haze if the light is right, but other than that, it doesn't seem to smoke.

You can smell it though haha. Smells like you'd expect something burning oil to smell like.
Well my plans changed last night unexpectedly so I didn't get to work on the mirrors like I wanted.

But I also have a line on some turbos, intakes and exhaust manifolds off a 6.5 motor that my buddy in Ohio has. I'm buying those off him and will rebuild the two turbos, keep the better one, and then sell the rest to likely pay for the whole setup and then some.

Not sure when I'll attempt the install, but I'm going to start soaking the manifold bolts now and spray them a few times a week so hopefully the bolts will come out.
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Mirrors are being media blasted today, so I should be good to get them primed tonight. I was going to just sand them down, but the media blasting is much easier and will remove any traces of rust and surface impurities.

My main hope is that the media isn't too aggressive and puts pits in the metal. Not a huge deal if it does, but it would add some extra steps.
Mirrors are all painted and installed. I wanted to match the paint that is on the bumpers and wheels, but couldn't find any locally. I need to pull the mirrors off again anyway so I just gave them a coat of satin black for now.

They look much better on there. Visibility is obviously reduced from the other mirrors, but that was expected haha.
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Looks great!

I thought you were after the late 70s model mirrors?

Sent from my motorola one 5G UW ace using Tapatalk
I was, and still am, but these were free so I figured I'd run them for a little while haha.

I haven't found a decent source for the other, larger style mirrors yet that I can see what they look like before buying.

I eventually need to get down to the junk yard and see of they have any of these trucks left in there.

I may just bite the bullet and order a set off LMC or something and hope that they are what I'm after.
Tomorrow is the first big test for the fuel mix.

Taking it to work so I'll see how it runs compared to before. I have driven it around the neighborhood and let it idle some and it seems to be doing fine. May sound crazy, and maybe it's just my mind playing tricks on me, but the truck seems to have more pep with this oil/fuel mixed.

But it's hard to tell until I pull the big hill by work. That'll be the determining factor as to how it runs.
Made it to work without issue. Runs great. Power is ever so slightly more noticeably better off the line. Also seems to run at higher rpm slightly smoother. Pulling the hill was about the same.

My guess is that the little bit thicker fuel is compensating for the 36 year old injection pump.

It was down to 30⁰ last night and I did note that it started slightly harder than it normally would, likely due to that oil being thicker. But oddly enough it smoked less on startup than straight diesel did lol. That part makes no sense. But once up to temp I get zero smoke at all. That haze goes away entirely, only indication something is different is the smell.

So I think I'm going to mix another batch and try half a tank.
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Mixed another batch tonight. Did a full 5 gallons this time, which put me right around half a tank.

I had to stop and get a little diesel today otherwise I wouldn't have made it home lol. I had to do a little extra driving to get a co-worker home since her transmission in her car decided to have 4 neutrals.

I went a touch heavier on the oil this time to see what happens, and since I had about 5 gallons of diesel in the tank anyway.
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New fuel seems to be fine. Definitely have a slight haze when cold. But once warm it goes away. Still runs nice and smooth (for a 6.2 lol).

So that's about 3 gallons of diesel, 4 gallons oil (used 15w40 amsoil out of my 15) and then a gallon of that gas/diesel mix.

I think come summer I can definitely run a 80/20 mix of oil to diesel mix without issue.
Thats nice to be able to buy less fuel and get to reuse the oil that you have already paid for
Not sure how I missed this project thread. Love me some fun squarebody trucks. Following along now. :)
Good change on the mirrors. (y)
Yeah as I sit now, I still have about 40 gallons of that diesel gas mix left. And then I have another 20 gallons of waste oil at home. Some if it I can't use due to contamination. But I can get as much as I could ever need from work lol.

So in theory I have enough to last me a while since on a full tank, at say a 70/30 mix, I'd be using 6 gallons of the gas diesel mix. Which means I'd need 14 gallons of oil per full tank.

So as long as I have the oil, the diesel mix I have left will get me roughly 6 tanks. But that also means I'd need 84 gallons of oil haha. But 6 tanks will last me at least until mid summer with how much I drive this truck. I usually only fill it once every two weeks at most. And that's with driving it often.
So got some updates. Went out to visit my buddy in Ohio last weekend and he ended up giving me the 6.5 turbo parts.

So I have 2 turbos, 2 upper and lower intakes, oil lines, and the passenger side manifold.

One turbo needs to be rebuilt, but I'll likely do both since the kits are cheap. Once I unload it all I'll pics.
Here's all my parts. I was able to get both turbos apart and assess their condition. The one that I am using just needs to be rebuilt with new seals and bearings.

The other one that had excessive shaft play will need a new turbine wheel, which means a whole new shaft. I'm not sure if I'll end up doing anything with that one or not yet. Depends what I can find the parts for price wise.

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