1952 XM211 Repower / Powertrain Swap

[Valley Rock]

Will I be burned at the stake here for repowering an original truck ?

So I have a 1952 XM211 that is completely stock original Powertrain wise .

It has the 302 6cyl Jimmy and cadillac auto trans with the Hi/Lo on the back of it, and a single speed in/out T-case .


This truck is a water Tender, and was in Civil Defense from the time it left the military up until somewhere in the 90s .

Truck has been setting the last ten years or so, but will start up and drive right now, I have driven it down to the gas station and put fresh gas in it .


So why do I want to change the Powertrain ?

I am going to be using this truck daily up in the woods during forest fires, and I need it to be dependable (manual trans) and prefer it to be a diesel engine and the T-case do the reduction work .

I have not heard good things about the Hydramatic and don't have much faith in it's ability to not let me down eventually .

I already have a 6cyl turbo diesel engine sitting here with a 6 speed trans hanging off the back of it, the engine is the same length as the gas engine that resides in the truck now so that should work fine, I also have spare M35A2 Transfer cases so I am thinking I could use one of those, this is all a rough draft inside my head .

The replacement diesel engine has a 12v starter, and so I am leaning towards making the entire truck 12v as i can't see any reason to keep it 24v .


Obviously this isn't something that's going to happen over night, but it shouldn't take too long I hope as i need it going by the end of May .

I am open to suggestions and opinions on all of this .

(Hope I posted this in the right spot)

 

[NDT]

M35A2 transfer case front axle output shaft spins wrong way for the GMC front axle.

 

[Valley Rock]

Here are a few pics ...

 

[SturmTyger380]

Nice truck! I think most of us G749 folks have thought at one time about a re-power. As the parts dry up for the Hydramatic transmissions, any of us that want to keep driving will possibly face a re-power situation.

We complain about the transmissions but they can be tough if taken care of.

 

[m1010plowboy]

Early Deuce re-engine

Hey welcome aboard, you're kinda new around here so let's get you a beverage and see if we can help. I'm the President of a Civil Defence Museum so I like your truck. You'd actually be doing a favour to someone who is trying to repower with an original drive-train. If you go by the book, motor, transmission and radiator come out as a complete package. If you grab a short video of it running, driving, shifting, reverse, .....first you'll shock a few folks because that's a cool truck, then I'm sure you'll have a trailer drive under it while you're pulling it.

For a raw 6x6 platform it's very capable, flexible, incredible low ratios the way it is so a new diesel, dual circuit brakes, front differential to adapt to a new transfer case and different rubber, she'd be a bull-dog. Breaking stuff on a 50's truck is a problem unless you have a supply of axles and other consumables. Some contracts ask us to run 10yr old equipment and newer partly for that reason.
Check the frame at the suspension mounting points for cracks. We've seen fatigue at the back hanger on the front frame contact. After pulling boxes and checking frame rails we have found some twisting and arching. Emergency Brake Drum can heat, crack and detonate so re-thinking this component would be required.
The small cab, difficult access/egress can be a problem. Just yesterday I buried my pick-up and had to stuff a 70 year old, 6'2" neighbour into the deuce to pull me out. If you can't bend your knees to your ears this is a tough truck to get into.

It's horrible in tight spaces in the bush. Without power steering it won't dry steer and 50 point turns happen often. Power steering would be nice.

I've been feeding parts to a guy working on a cummins and he will have the truck running one day. The steps to getting rolling are many but it can be done. If you jump on it make sure to take us along for the ride with plenty of photos. I'd love to see more of the pump, pto, tank set-up. That's a pretty rare beast from a Civil Defense aspect so grabbing pictures and storing them at one of the U.S. CD museums would be real cool. http://www.civildefensemuseum.com/

 

[Carboarius]

As NDT said above the M35A2 transfer case front output spins the wrong way, and only has one rear output. The Jimmys have two driveshafts going to the rear. I had the same concerns as you getting into these trucks, but as long as they are taken care of they are as dependable if not more than the M35s. The Jimmys even have a few features that are arguably better than the M35s, for instance the dual wheel cylinder brake system and the rear overload springs that are the same size as the primary springs. My stock powertrain in my 1954 M211 has never let me down and fires right up consistently, its even gotten me out of places I probably shouldn't have gone.
As for swapping power packs over, it is quite a process and you may not get it done in time for May.
If you do choose to swap you might as well convert to 12v as you'd have to change gauges anyway, and swapping bulbs is easy.
What ever you decide to do, please post pictures, as I am sure we are all intrigued.

 

[gentrysgarage]

I will be flipping the front axle and rotating the pinion down on my truck's front axle. My set up is 6BTA, Eaton FSO-6046 and a Ford NP205 transfer case. It will be used for hauling stuff, but not lugging a bazzilion pounds of water up hills and dales so the NP 205 is too light duty for you. Just some things to think about.

 

[kubotaman]

For your needs, I think you want a newer truck

 

[M37keppy]

I use a m211 with a dump hoist under the bed for moving grain. It regularly scales out at about 36,000. So if you take care of the maintenance it’s a tuff truck

 

[Valley Rock]

Thanks for the input Plowboy, I'm not sure how the radiator is supposed to come out as a unit with the engine, but either way it will come out, I will have someone ride around and make a vid for you before it comes apart, if this truck had a manual trans and a Hi Lo T-case I would not go to all this effort, but I have zero faith in that trans and i need a dependable vehicle that will be considerably better when i'm done .

This truck is in pretty much mint condition, I doubt it has never had a hard day in it's life, there is litteraly not even a dent in this truck and has been "Gov. maintained" all it's life .

I plan on adding Hydro assist steering in the future to avoid the Austin Powers turn arounds, the Diesel engine already has a pump on it and I have two old Ford Hydro assist setups lying here with the control valving, probably won't happen this year, but shouldn't be overley difficult to add on at some point to make it a more driveable unit .

So at this point I think I will leave the T-case in place, removing the engine/trans and replacing them with the Diesel engine and trans, make a driveline and see how that works, I don't know the 1st gear ratio of this trans nor do i know the 1st gear ratio of the Caddi trans but with a manual it just might work out ratio wise, and since it has a weird T-case along with everything else I am kind of stuck with it for now, If it's not low enough for the woods then I will figure out something else, but the gas engine and auto have got to go so this will be the first step, I very much appreciate everyones input and hope it will continue .

IF the truck is not low geared enough to work, I have an M50 that can work till it is, was just hoping to have both trucks ready for fire season in case I hire another driver OR need a backup truck .


Questions:

The Rockwell axles are not self lubing, you have to pack the wheel bearings, are the Eatons the same way ?

What is the ratio of the Eaton axles ?

If the M35A2 T-case spins the wrong way, why can't I put it in backwards ?

Haha, I have more questions but I have to get back to work, here is a few more pics ...

 

[NDT]

Eaton axles? The GMC has General Motors corporate axles. With grease lube wheel bearings. The 3rd member on the front axle points to the rear, on the M35A2 Rockwell axles, they are "top loading" and all spin the same direction.

 

[Carboarius]

The GMC axles are 6.17:1 ratio and the GMC t-case is a 1.16:1 ratio

As for the Hydramatic transmission, the ratios are as follows:

Gear High range Low Range
1st 4.08:1 15.67:1
2nd 2.63:1 10.05:1
3rd 1.55:1 5.95:1
4th 1.00:1 3.82:1
Reverse 4.54:1 17.35:1

 

[Valley Rock]

Eaton axles? The GMC has General Motors corporate axles. With grease lube wheel bearings. The 3rd member on the front axle points to the rear, on the M35A2 Rockwell axles, they are "top loading" and all spin the same direction.

Huh, it was my understanding that these are Eaton 110s, I know GM and Eaton were tied up at some point, but yes I understand the difference between the Rockwells and these, was just hoping that these were gear oil lubed, vastly superior system to the grease IMO, do you know the gear ratio ?

 

[Valley Rock]

The GMC axles are 6.17:1 ratio and the GMC t-case is a 1.16:1 ratio

As for the Hydramatic transmission, the ratios are as follows:

Gear High range Low Range
1st 4.08:1 15.67:1
2nd 2.63:1 10.05:1
3rd 1.55:1 5.95:1
4th 1.00:1 3.82:1
Reverse 4.54:1 17.35:1

Ah, forgot to refresh before posting, thanks for this info !

 

[Carboarius]

deleted

 

[NDT]

From TM9-819

 

[m1010plowboy]

Just another axle

There are a pile of suppliers listed that built the G749 series but Eaton and Rockwell aren't on the list. As reported, GM Truck and Coach plant has it's face on these 50's 6x6 rear-ends. Did Rockwell take over the GM diff line? When? If only there was some way I could find out. Alexa..........Alexa....oh ya, I don't have Alexa.



Looks like the process is easier with the cab off but this is what it looks like. Mattech hung out with the field boys that said 4 hrs is enough for a Removal and Replacement.....R&R.

The engine can be sitting on a test stand, full of fluids and ready to go. When you pull it you don't even need to drain any fluids. If we're sharp, just as your picker truck is pulling it out of the frame, we set it right on Paul's trailer. Not sure who Paul is but I needed a name for the story.



Besides the Civil Defense thing, your truck is still a better candidate for a re-motor than a complete/original that has been sitting in a field for 40 years. It's not really an early number, October 52, it's already been chopped up, welded on, hauled heavy so a little more heart driven into it would be a great way to finish. A person could always go out and get one of those fancy brand new 737max's or a Bobcat S570 and have something new fail on you the first day. At least this way, you'll know every nut and bolt. Get'er done.

 

[Valley Rock]

I had some time today so I drove it around a made a couple vids for you guys, here's one, I'll post the other if I can get it to load .

https://www.youtube.com/watch?v=LLlQ8aE-2ls&t=10s


So I never could get that other vid from yesterday to load, so I made another, It's worse than the one above, so click on it if you think you might enjoy watching me driving around an old cool truck .

Peace & Bacon Grease .


https://www.youtube.com/watch?v=dDc7HocnF8E&t=8s

 

[m1010plowboy]

My jaw is sore from smiling, thanks for the ride. It's too bad you can't 'run what you brung', service it, strap cameras on it and take us to work the way it is. Kinda like a Plane Savers video only "Deuce Savers" video. Mikey's raised about 24 grand in just a few months.

https://www.youtube.com/watch?v=PEo64-a5DZs


That truck is historic. I get the reliability thing and having it break and burn would suck too. Watching it go fight fires though, almost 70 years old, 50's GM technology, what a story.

I just found a thread that I thought was posted last month but apparently it's 4 years old so time really does fly.

This truck was still in service 4 years ago which isn't too bad considering the size of tank on it.
https://www.steelsoldiers.com/showthread.php?58040-The-unofficial-g749-picture-thread/page17

 

[Merle]

deleted.......