Looking for ideas on an alternate manual transmission for my m35a2

[WoodyUSMC]

I know this has been discussed but it always seems to get off track and I can't seem to find answers. Yes I've search a lot!

I'm starting a crew cab build and will be pushing the rear axles back at least 18". I was thinking about doing a brownie box but would prefer to not to. I was hoping to find a transmission that would have an OD closer to 0.70. Even if that means moving the transfer case back.

I am also trying to figure out what motor I want. Cat, Cummins or DT466. So any legitimate advise would be great

Disclaimer: I will be doing full disc brakes

Please no lectures on why I can't or shouldn't do it.

 

[rustystud]

If your moving the whole rear suspension system back 18" then you can go with a ton of different transmissions. Fuller 7,9,13 speeds, Clark 5,7,9 speeds, the list goes on and on. You can even go with an Allison automatic if you so desired. It all depends on how much you want to spend. Same goes with the engine. I would stay away from CAT for now though. Lately they have had serious issues with their engines going back to the C-7's . I would use the DT466 as it has a proven track record of excellent performance. Cummins engines are OK, though it depends on which model your going to use. ISC, ISL, ISM all have a lot of electronic issues, and injection pump problems. I know as they are the most common engines used in the transit industry and I have personally worked on each model. Now the M11 is a great engine if you can find a good used one.

 

[WoodyUSMC]

If your moving the whole rear suspension system back 18" then you can go with a ton of different transmissions. Fuller 7,9,13 speeds, Clark 5,7,9 speeds, the list goes on and on. You can even go with an Allison automatic if you so desired. It all depends on how much you want to spend. Same goes with the engine. I would stay away from CAT for now though. Lately they have had serious issues with their engines going back to the C-7's . I would use the DT466 as it has a proven track record of excellent performance. Cummins engines are OK, though it depends on which model your going to use. ISC, ISL, ISM all have a lot of electronic issues, and injection pump problems. I know as they are the most common engines used in the transit industry and I have personally worked on each model. Now the M11 is a great engine if you can find a good used one.

Thanks Rusty! I almost sent you a message directly on this. Now with the fuller or the clark I'll still be able to use the differential so long as i move it back. I'd love to find a good rebuilt DT466.

 

[WoodyUSMC]

If your moving the whole rear suspension system back 18" then you can go with a ton of different transmissions. Fuller 7,9,13 speeds, Clark 5,7,9 speeds, the list goes on and on. You can even go with an Allison automatic if you so desired. It all depends on how much you want to spend. Same goes with the engine. I would stay away from CAT for now though. Lately they have had serious issues with their engines going back to the C-7's . I would use the DT466 as it has a proven track record of excellent performance. Cummins engines are OK, though it depends on which model your going to use. ISC, ISL, ISM all have a lot of electronic issues, and injection pump problems. I know as they are the most common engines used in the transit industry and I have personally worked on each model. Now the M11 is a great engine if you can find a good used one.

I looked up gear ratios for the fuller 6 speeds. The T0-955AL and ALL show an OD of 0.65. That seams pretty good to me but I think what I'll need to a list of models to look for. and hit up the wrecking yards here in Spokane.

 

[rustystud]

I looked up gear ratios for the fuller 6 speeds. The T0-955AL and ALL show an OD of 0.65. That seams pretty good to me but I think what I'll need to a list of models to look for. and hit up the wrecking yards here in Spokane.

Don't just limit yourself to Spokane. Out here near Seattle, there are tons of wrecking yards with hundreds of medium to large truck transmissions laying around.

 

[WoodyUSMC]

I hear you there. How har do you think it would be to marry up a t955 to a dt466?

 

[rustystud]

I hear you there. How har do you think it would be to marry up a t955 to a dt466?

It would be pretty simple. The problem is the "width" of this transmission. Since it is a "twin countershaft" unit it is really wide. The deuce's brake assembly would have to be moved if you tried to install this transmission. Yes this transmission would be a great unit in a deuce though it is a bit overkill . At 950 ft Ibs of torque it is rated well above anything you would really need. I personally would look for a "smaller" transmission. Maybe one that is not a twin countershaft unit due to width issues. Also this transmission is an "expensive" one to rebuild. When I was still working on them back in the day, they would cost easily over $2000.00 just in parts. I don't how much you would spend in todays money. They are nice though in that if you want an "overdrive" unit, you just swap the "fifth" gear set with the "drive gear set" gear set. No need to buy anything but a gasket kit !

 

[fasttruck]

A problem to solve would be, if you wish to preserve the all when drive, is the rodded shift linkage between the transmission and the transfer case which keeps the transfer case oriented to which direction the transmission is going. This function on a 809 series etc is air operated with valves on both the transmission and the transfer case.

 

[WoodyUSMC]

It would be pretty simple. The problem is the "width" of this transmission. Since it is a "twin countershaft" unit it is really wide. The deuce's brake assembly would have to be moved if you tried to install this transmission. Yes this transmission would be a great unit in a deuce though it is a bit overkill . At 950 ft Ibs of torque it is rated well above anything you would really need. I personally would look for a "smaller" transmission. Maybe one that is not a twin countershaft unit due to width issues. Also this transmission is an "expensive" one to rebuild. When I was still working on them back in the day, they would cost easily over $2000.00 just in parts. I don't how much you would spend in todays money. They are nice though in that if you want an "overdrive" unit, you just swap the "fifth" gear set with the "drive gear set" gear set. No need to buy anything but a gasket kit !

This is proving to be quite a challenge. I agree the width would be an issue as well as its much more transmission than I really need. But thus far I have been unable to find info on anything smaller that would fit and have an OD of .7-.6. I'm sure there is something out there. And if I really had to I could go to an automatic. But I'd really like to stick with a manual.

 

[WoodyUSMC]

A problem to solve would be, if you wish to preserve the all when drive, is the rodded shift linkage between the transmission and the transfer case which keeps the transfer case oriented to which direction the transmission is going. This function on a 809 series etc is air operated with valves on both the transmission and the transfer case.

I'm trying to wrap my mind around what you mean in my application. When I removed the stock transmission there was no such rod CONNECTING the two. Maybe that is not how the M35a2 was done?

 

[41cl8m5]

I think he is referring to a duece with a sprag transfer case. There is a shaft that disengages the sprag clutch for the front axle drive that attaches to the transmission. If you have the air switch transfer this hook up is not used. It still on the transmission just hangs out there.

 

[WoodyUSMC]

I think he is referring to a duece with a sprag transfer case. There is a shaft that disengages the sprag clutch for the front axle drive that attaches to the transmission. If you have the air switch transfer this hook up is not used. It still on the transmission just hangs out there.

I have the air transfer. Thank you for clearing this up.