M1031 to M37 drivetrain

[noodlehead333]

I'm contemplating buying a m1031 on GL and transplanting the NP205, front axle, and rear axles to my M-37/4BT/NV4500 project. Any advice or warnings? From measurements at the local u-pull-it this will widen the track width. I may or may not widen out the fenders depending on how it looks. Anyone?

 

[mattveeder]

The best advice that I can give is to do it asap. Allthough I enjoy my "stock" m37 they have next to no power and thats why mine only gets a few miles a year. As for the swap I have seen it done a few times and it seems to be pretty straight foreward.

 

[noodlehead333]

Yeah, my M37 is fun to drive around town and down the trails but doesn't have any real power. It's gonna come down to whether I can get an M1031 for relatively cheap (both cost of the truck itself and within a reasonable distance to me).

 

[mattveeder]

You will find it. I always seem to find these type of things at the worst possible times. It seems like they show up at the same time as we need to put money in our house and other bad times. But that doesnot always stop me. (My wife hates it when I do it)

 

[Tanner]

Why not just move the body/cab/bed/fenders to the GM chassis? You're not far off from creating that with what you intend to do. And the 4BT would probably fit the GM chassis easily/easier with the proper mounts...

'Tanner'

 

[mattveeder]

Swaping the body always has it own obstacles like swapping drivetrails. For example wheel base, steering colunms and other things. In my expierence I've been able to keep some of the original "character" with just swapping drivetrains.

 

[noodlehead333]

You will find it. I always seem to find these type of things at the worst possible times. It seems like they show up at the same time as we need to put money in our house and other bad times. But that doesnot always stop me. (My wife hates it when I do it)

Boy, you aren't kidding!! I always find the parts at EXACTLY the time when we have "higher priorities". I've endured the wrath of my wife on more than one occasion. But it's never stopped me from looking. And it never will.

As for swapping the body to the Chevy frame, I want to keep as much of the M37 original as possible. The frame looks good. But I'll see when I finally get it all apart. If it makes sense to transfer the body to the Chevy frame, then that's what I'll do. But I'm going to try to work with the original frame if it's viable.

 

[nattieleather]

The rear axle will go in with little to no fus. You will need to remove the spring perches and center the axle and then reweld them on for fit. The front on the other hand is a different story. You have three options. Because the passinger side spring perch is a part of the differential you can A: shorten the driverside axle housing to fit requiring the housing and the axle shaft to be shorten. B: Move the passinger side spring outboard of the frame requiring some engineering, but will allow you to keep the stock steering set up. Or C: completely reengineer your steering to the inside of the frame and engineer both your front springs to the outside of the frame. I went with option B when I put M880 axles on my M37. Still in the garage in a state of can't get time and money to play nice with each other...

 

[noodlehead333]

Yeah. Every time I schedule time to work on my M37 my wife comes up with something I "need to do". Not because she doesn't want me to work on it but because she thinks I might find SOMETHING ELSE TO BUY.

 

[citizensoldier]

Just a thought? If your going to put a 4BT in it anyway why not just do all the standard upgrades that go along with that swap?? 4.89 gears, keep the T case, disc brake upgrade, and power steering upgrade?? I would think this would be about the same or not much more than the price of a M1031 these days. Just asking and not trying to poop on your parade..

 

[Varyag]

Have you tried looking at a salvage yard for a 1 ton pickup? Maybe way cheaper to clean out a junker of parts then get a cucv and tear it apart. Even if you have to rebuild stuff.

 

[noodlehead333]

I want to make my M-37 highway capable. Even with 39 in tires and 4.89 gears it would be doing close to 3k at 65 mph. NOT GOOD for a diesel engine. For that reason, I'm going to try to find a 3.73 or 4.10 ratio set of axles. I also want the NP205 primarily because of parts availability. Another reason for wanting to swap axles is the disc brake upgrade is a LOT cheaper. I'm also hoping to be able to salvage additional parts (like a welder or compressor) from the 1031. Just my justification for trying to find a 1031.

 

[noodlehead333]

Have you tried looking at a salvage yard for a 1 ton pickup? Maybe way cheaper to clean out a junker of parts then get a cucv and tear it apart. Even if you have to rebuild stuff.

Yeah I am making almost weekly trips to the local yards. I can't find salvageable 4x4's. It seems like anyone with a junkable (is that even a word?) 4x4 rips it apart and reuses the parts himself/herself or sells the parts on Craigslist and wants $600 or more per axle. At least around here.

I am keeping my eyes and ears open for other ways to get the parts I want. The 1031 is just a "all-in-one" solution.

 

[greentoys]

I just finnished putting an M37 body onto a 90 Dodge 3/4 ton chassis w/ Cummins 6bt. The problem with putting the M37 body onto most civy frames is the frame height and kickup under the cab and over the rear axel. This force the body to "lifted" about 6'. you may like the look or may not.
also, look out for which side the front driveshaft is on. I think most GM and Ford are driver side and Dodge is pass, Same as M37. the stock M37 is pass side and the engine is offset about 1 3/4" to the drivers side of the frame to make more room for the driveshaft. So you might consider that when instaling the 4bt. My M37 now has 3.07 gears and a 727 tranny.
I'd like to post pictures, but using dialup internet and my connection speed is usually 24k... yes 24k. today when on SS i click a thread and it takes one minute to open. I'm laid off now but, as soon as I get a Job I'm going to get some type of antenna for internet. they cost around $350 to $500. I don't have high speed service where I live even though I'm only 9 miles from a town of 100,000.

Ray

 

[frodobaggins]

I just finnished putting an M37 body onto a 90 Dodge 3/4 ton chassis w/ Cummins 6bt. The problem with putting the M37 body onto most civy frames is the frame height and kickup under the cab and over the rear axel. This force the body to "lifted" about 6'. you may like the look or may not.
also, look out for which side the front driveshaft is on. I think most GM and Ford are driver side and Dodge is pass, Same as M37. the stock M37 is pass side and the engine is offset about 1 3/4" to the drivers side of the frame to make more room for the driveshaft. So you might consider that when instaling the 4bt. My M37 now has 3.07 gears and a 727 tranny.
I'd like to post pictures, but using dialup internet and my connection speed is usually 24k... yes 24k. today when on SS i click a thread and it takes one minute to open. I'm laid off now but, as soon as I get a Job I'm going to get some type of antenna for internet. they cost around $350 to $500. I don't have high speed service where I live even though I'm only 9 miles from a town of 100,000.

Ray

You can't drop a bomb like that without pictures or a good build thread.



edit: Sorry, saw "dialup"

 

[nattieleather]

Dodge up till 92 I think were passinger side drop then in 93 (when they changed the body style) they went to drivers side drop on the front axle. Ford has always been drivers side drop. GM has always been Passinger side drop. M37s are Drives side drop. If your changing the axles and the Tcase just make sure they come from the same truck and you'll be all set.

 

[noodlehead333]

Yet another argument for pulling all the applicable parts from one truck. I've got to keep looking though. Lately the M1031s are going for 2k to 3k. I'd be willing to pay that but with transport costs (I am going to go pick it up) I'd be looking at 4k. That's a little too rich for my blood right now. It's a long term project and I have plenty to do (still gotta inspect and rebuild the NV4500 and 4BT). Plus my M37 is still running and it's hard not to drive it.

 

[mattveeder]

It sounds like you are talking like me. But in my past expierences it all has seemed to fall together at the right time.

 

[noodlehead333]

It sounds like you are talking like me. But in my past expierences it all has seemed to fall together at the right time.

Thanks. I keep working at it and it's slowly (I repeat SLOWLY) progressing. Even if I can only sand down a small part or clean off something, I don't miss more than a day or two. I just keep jumping around about what I want to do first. But I love every minute I work on any of it. Thankfully I got my weekends back starting two weeks ago. It should start progressing a little faster now. I hope.

 

[m376x6]

Dodge up till 92 I think were passinger side drop then in 93 (when they changed the body style) they went to drivers side drop on the front axle. Ford has always been drivers side drop. GM has always been Passinger side drop. M37s are Drives side drop. If your changing the axles and the Tcase just make sure they come from the same truck and you'll be all set.

M37's and M43's fronts are passenger side drops. The rear ends are shifted to the passenger side as well.