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M35a2 automatic transmission swap?

neomadic

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Other alternative is to look for an overdrive transfer case to couple to the direct drive Allison to increase speed like the m939 trucks did. There are several od spicer cases. The t1138 is too big for a deuce not to mention 2000$ cause of demand
Any idea on what the part numbers of those OD Spicer tcases would be?
 

rustystud

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Coming in late to this party, but the best transmission would be the Allison 1000 found behind a 4X4 Chevy with a DuraMax.
Not only will you have the transfer-case adapter on the transmission, but you can buy an adapter to fit a NP205 transfer case to it. The latest Allisons can handle well over 800 HP now. With all the special upgrades this transmission can have, you can increase that easily to 2,000 HP.
My stock Chevy (Silverado 3500HD) has an LP5 DuraMax putting out 500HP factory. The Allison behind this engine can handle that power easily. That is way more then you need for a Deuce. I'm in the process of building up an Allison 1000 for my Deuce. The biggest problem is the transfer-case. I'm going with the NP205 since there is already an adapter on the market to fit it behind the Allison. I've bought two and I've bought the special gears for NP205 transfer-case to beef it up to handle 2,000 HP also.
Now I just need the time to put everything together.
I'm still finishing up building my shop, so I'm hopeful that by the end of summer I can start work on the Deuce again.
I will be using my MultiFuel engine. I bought an adapter years ago to fit an AT540 transmission behind it. If I could afford it, I would just put the whole power package from a Chevy with the DuraMax in the Deuce. The problem is the Duramax's go for over $7,000.00 used !
 
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DB556

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Coming in late to this party, but the best transmission would be the Allison 1000 found behind a 4X4 Chevy with a DuraMax.
Not only will you have the transfer-case adapter on the transmission, but you can buy an adapter to fit a NP205 transfer case to it. The latest Allisons can handle well over 800 HP now. With all the special upgrades this transmission can have, you can increase that easily to 2,000 HP.
My stock Chevy (Silverado 3500HD) has an LP5 DuraMax putting out 500HP factory. The Allison behind this engine can handle that power easily. That is way more then you need for a Deuce. I'm in the process of building up an Allison 1000 for my Deuce. The biggest problem is the transfer-case. I'm going with the NP205 since there is already an adapter on the market to fit it behind the Allison. I've bought two and I've bought the special gears for NP205 transfer-case to beef it up to handle 2,000 HP also.
Now I just need the time to put everything together.
I'm still finishing up building my shop, so I'm hopeful that by the end of summer I can start work on the Deuce again.
I will be using my MultiFuel engine. I bought an adapter years ago to fit an AT540 transmission behind it. If I could afford it, I would just put the whole power package from a Chevy with the DuraMax in the Deuce. The problem is the Duramax's go for over $7,000.00 used !
Rusty, what computer are you using to control the allison 1000?
I know this is going to need a Throttle position sensor to get tied into the linkage for the multifuel throttle.
 

rustystud

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Rusty, what computer are you using to control the allison 1000?
I know this is going to need a Throttle position sensor to get tied into the linkage for the multifuel throttle.
There's a company in Indiana (Fleece Performance) that can modify any controller for the Allison. I'm sticking with a 5 speed configuration as two over drive gears would be too much for a MultiFuel to handle. Not enough torque to pull that second over-drive gear.
As far as a throttle position sensor goes, you can find them on eBay for under $50.00.
I already had my NP205 transfer-case modified to except a speed sensor for the Allison's road speed sensor input.
 

TechnoWeenie

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I didn't want to start a new thread so I guess I'll post a related question here....

Most of these trans mods are talking about are paired with an engine change.


What about the stock LDT?

IIRC, isn't one of the biggest issues with the LDT is that there's nothing that bolts up, and adapters have to be custom made?
 

neomadic

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I didn't want to start a new thread so I guess I'll post a related question here....

Most of these trans mods are talking about are paired with an engine change.


What about the stock LDT?

IIRC, isn't one of the biggest issues with the LDT is that there's nothing that bolts up, and adapters have to be custom made?
Yep. It's very difficult to mount anything but a 3053/3052 to a LDT. I thought, "I'll just build new mounts and use a LDS flywheel housing..." Nope. It offcenters the motor towards the passenger side and tilts it 84 degrees towards the driver's side. I'd have to redo my fan shroud, upper radiator mount, re-route the starter wires, and make new front and rear engine mounts.

Back to trying to figure out how to make a LDS flywheel work in an LDT flywheel housing, figuring out the right thickness of starter spacer, and designing a LDT to SAE #2 adapter of the correct thickness to allow me to hang a FS06406 off it using a 15" push single disc clutch instead of the dual 14" pull clutch that the transmission input shaft is designed for. I'll have to build a new front bearing retainer with the release bearing sleeve for the 6406 and make a custom release bearing holder too.

All of this work to get rid of that 3-4 gap! lol! I'm starting to think getting a 3052 and a gear vendor overdrive or 5831 brownie box would be smarter, but with the motor upgrade and the weight of my rig, making the six speed overdrive trans work just makes more sense. I want my weak links to be ujoints, not 2nd gear..
 

rustystud

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Yep. It's very difficult to mount anything but a 3053/3052 to a LDT. I thought, "I'll just build new mounts and use a LDS flywheel housing..." Nope. It offcenters the motor towards the passenger side and tilts it 84 degrees towards the driver's side. I'd have to redo my fan shroud, upper radiator mount, re-route the starter wires, and make new front and rear engine mounts.

Back to trying to figure out how to make a LDS flywheel work in an LDT flywheel housing, figuring out the right thickness of starter spacer, and designing a LDT to SAE #2 adapter of the correct thickness to allow me to hang a FS06406 off it using a 15" push single disc clutch instead of the dual 14" pull clutch that the transmission input shaft is designed for. I'll have to build a new front bearing retainer with the release bearing sleeve for the 6406 and make a custom release bearing holder too.

All of this work to get rid of that 3-4 gap! lol! I'm starting to think getting a 3052 and a gear vendor overdrive or 5831 brownie box would be smarter, but with the motor upgrade and the weight of my rig, making the six speed overdrive trans work just makes more sense. I want my weak links to be ujoints, not 2nd gear..
Our Deuce already has a "SAE" adapter for the Spicer transmission. That is how my Allison will adapt to the engine. The problem is the "flywheel" which I have. It was designed to fit the Allison 540 transmission which corresponds to the Allison 1000/2000 transmission. I was going to have my machine shop friend make my stock Deuce flywheel into the "automatic" one, but he retired last year.
So that means I only have the one "special automatic" flywheel.
If I had the money, I would have another machine shop make one and post the dimensions here. Since I don't I will just build this "one off" truck and see how it drives.
 

neomadic

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Our Deuce already has a "SAE" adapter for the Spicer transmission. That is how my Allison will adapt to the engine. The problem is the "flywheel" which I have. It was designed to fit the Allison 540 transmission which corresponds to the Allison 1000/2000 transmission. I was going to have my machine shop friend make my stock Deuce flywheel into the "automatic" one, but he retired last year.
So that means I only have the one "special automatic" flywheel.
If I had the money, I would have another machine shop make one and post the dimensions here. Since I don't I will just build this "one off" truck and see how it drives.
Sorry if its been covered or suggested. I've been reading my eyes out lately, but will this flywheel help you? It was used in the m656 xm757 to mount an Allison behind a LDS465-2


I need one of the flywheel housings but not the flywheel/flexplate. I'd like to find one here in AZ if I can.
 

TechnoWeenie

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Sorry if its been covered or suggested. I've been reading my eyes out lately, but will this flywheel help you? It was used in the m656 xm757 to mount an Allison behind a LDS465-2


I need one of the flywheel housings but not the flywheel/flexplate. I'd like to find one here in AZ if I can.

I guess that begs the question... WHICH allison trans?

EDIT: Looks like the Allison TX200-6 ...

So, what other Allison trannys can be bolted up with that adapter?
 
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gringeltaube

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I guess that begs the question... WHICH allison trans?

EDIT: Looks like the Allison TX200-6 ...

So, what other Allison trannys can be bolted up with that adapter?
Pretty sure that flywheel housing (of the LDS465-2) is a SAE #2. That means you would have many options - in theory...

Here is some good reading about the TX200-6 and possible alternatives...
 

rustystud

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Pretty sure that flywheel housing (of the LDS465-2) is a SAE #2. That means you would have many options - in theory...

Here is some good reading about the TX200-6 and possible alternatives...
Exactly. That is why you can use the Allison 1000/2000 series transmission behind the Deuce engine. The bell housings on these transmissions all come off and you can get anything from a SAE 1 to SAE 3 adapter for them. Of course the Chevy bolt pattern also if you so choose. Can you say DuraMax !
The flywheel is the key here.
 

neomadic

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Exactly. That is why you can use the Allison 1000/2000 series transmission behind the Deuce engine. The bell housings on these transmissions all come off and you can get anything from a SAE 1 to SAE 3 adapter for them. Of course the Chevy bolt pattern also if you so choose. Can you say DuraMax !
The flywheel is the key here.
If there's a relatively inexpensive way to go from the LDT non SAE pattern to a SAE#2 clutch housing, I'd love to know. There are only SAE#2 clutch housings available for the six and seven speeds that are the best matches for these trucks, and most of the bigger Allison stuff I've seen out there has all been SAE#2.

I'm going to give these guys a call in the morning and see what a custom spacer would run, just in case I can't make a LDS465-2 flywheel housing work.

 

gringeltaube

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If there's a relatively inexpensive way to go from the LDT non SAE pattern to a SAE#2 clutch housing, I'd love to know.
You can do that with a custom made spacer ring, after relocating (on the same BC) some of the holes on the LDT housing...
1669124758244.png

You will see that the "problematic" holes/studs only are 1; 2; 3; 5; 6; 7 & 13. Most have reinforcement bosses but even where there are none the material is about 13mm thick, which is as much as the Ø3/8" studs are screwed in, from factory. So that shouldn't be an issue.
 

neomadic

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If there's a relatively inexpensive way to go from the LDT non SAE pattern to a SAE#2 clutch housing, I'd love to know. There are only SAE#2 clutch housings available for the six and seven speeds that are the best matches for these trucks, and most of the bigger Allison stuff I've seen out there has all been SAE#2.

I'm going to give these guys a call in the morning and see what a custom spacer would run, just in case I can't make a LDS465-2 flywheel housing work.

Hayes wants $1500 for a sae adapter ring and they're 12-16 weeks out. Sad to see American manufacturing at this stage.
 

neomadic

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You can do that with a custom made spacer ring, after relocating (on the same BC) some of the holes on the LDT housing...
View attachment 884785

You will see that the "problematic" holes/studs only are 1; 2; 3; 5; 6; 7 & 13. Most have reinforcement bosses but even where there are none the material is about 13mm thick, which is as much as the Ø3/8" studs are screwed in, from factory. So that shouldn't be an issue.
The engineer in me doesn't like the fact that that adapter is aluminum and as thin as it is normally seeing that the whole weight of the transmision is hanging off of it. The Fuller FSO6406 is probably another couple hundred pounds heavier than a 3053 and quite a bit longer too.

I'm leaning towards cutting the ears of the 5ton flywheel housing and building a steel cradle mount for it. I can do that for free, in a day. I don't know how it didn't occur to me earlier.
 

gringeltaube

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The engineer in me doesn't like the fact that that adapter is aluminum and as thin as it is...
Forget that aluminum adapter; that image is only there to show the interferences.
I'm talking about relocating holes on the LDT flywheel housing itself, which BTW is as strong as the 5-ton housing and the same material, also.
And the 5-ton Spicer 6453 sure weighs a lot more too, and also hangs on the housing with its full weight.
Your custom adapter ring (MF-to-SAE#) can/should be made out of steel, of course. But $1500 for that is crazy...!
 

neomadic

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Forget that aluminum adapter; that image is only there to show the interferences.
I'm talking about relocating holes on the LDT flywheel housing itself, which BTW is as strong as the 5-ton housing and the same material, also.
And the 5-ton Spicer 6453 sure weighs a lot more too, and also hangs on the housing with its full weight.
Your custom adapter ring (MF-to-SAE#2) can/should be made out of steel, of course. But $1500 for that is crazy...!
That makes a lot more sense. Thank you for posting that image. It really helped visualize the difference.
 

TechnoWeenie

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So, to clarify...

One could - theoretically - bolt up a 1000 series Allisson auto, with an adapter plate and a custom flywheel?

So, we're looking at, what, 2K$?
 

neomadic

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So, to clarify...

One could - theoretically - bolt up a 1000 series Allisson auto, with an adapter plate and a custom flywheel?

So, we're looking at, what, 2K$?
There are SAE#3 bellhousings for the Allison 1000 so the transmission will bolt to the factory SAE#3 adaptor that came on the LDT465. You'd just need to find the right torque converter, and have the stock flywheel machined to bolt to it.

Figuring out the correct spacing between the flywheel and converter would be the tricky but not too hard part.

There's also the possibility that the flywheel flexplate from the LDS465-2 would work.
 
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