Allison MT41 questions

[sopicki]

Hello Newellers, I'm still putting together information on our "new" 1972 Newell Coach. Since we got no documentation with the coach, I'm trying to find information on the transmission. The data plate indicates that we have an Allison MT41SP. This was installed in 1981 along with an 8.2L Detroit turbo diesel engine. I would like to find an operator manual for information on what type of fluid to use and how often to change it, recommended methods of shifting, max temp's and use of the retarder (I've never used one). I've looked to e-bay, books4cars, Allison's web-site and about 10 different ways of Google search's, but I haven't found any info on the MT41. I have found info on the MT640 and 650 and have discovered that they superseded the 40's and 41's but not being familiar with the 41's or the 650's I wouldn't know what to follow and what to dismiss. Any help is appreciated. Thanks!

[rellick]

I could be wrong but I think they were a GM product, maybe try contact them? Those engines and trans were used in the older GMG trucks ect.

[sopicki]

I contacted Allison directly but since this is an obsolete transmission they no longer support it in any way and have sold the rights to the model to WW Williams in Ohio. I have contacted them and they are looking for information. They told me they'd call me back..... I was hoping that since this was a popular transmission in the 60's and 70's that someone would still have the books or some information on it. Thanks!!!

[rellick]

I contacted Allison directly but since this is an obsolete transmission they no longer support it in any way and have sold the rights to the model to WW Williams in Ohio. I have contacted them and they are looking for information. They told me they'd call me back..... I was hoping that since this was a popular transmission in the 60's and 70's that someone would still have the books or some information on it. Thanks!!!
Give this guy a try TKT Sales: Allison Transmission Parts Supplier (http://tktsales.com/index.php) he really knows his allisons

[sopicki]

Hello again. We've been working this week on rebuilding the brake system and while I have her up on jacks I decided to pull the transmission filter and change the transmission fluid. Since there isn't a drain plug on the pan, I assume that all that's required to drain the transmission is to remove the filter and let the system drain. Does anyone have experience changing the fluid on the Allison MT41 and care to share their experience? Will this drain the cooler as well? What came out was bright red and didn't smell burnt at all. The filter had a few metal particles in it but nothing alarming. 45824583For what it's worth, we pulled the Eaton 2 speed differential out of the housing (while the axles were out to work on the brakes) so we could re-seal it. The diff looks good but the hub bearings were toast. There was a lot of metal in the housing and the diff looks like it was a rebuilt unit. There was too much metal for it to be the hub bearings, the diff looks works and shifts great, so I'm guessing the metal was from a previous differential that died and the shop that replaced it never adequately cleaned the housing. It took me close to 3 hours to get the housing clean again. Hopefully we'll have her back on her tires by next Tuesday. Any advice on the the Allison or the Eaton is appreciated. Thanks!

[Dmatz]

In my boat we had to pump the fluid out through the dip stick. That got all the way into the drain pan. The pump is sold at west marine. Not sure if the pan drains into the filter or not.

[rellick]

I would pull the pan off the transmission, there will be oil in it, and probably some particles, Its a good time to change the gasket anyway. If the oil is nice and clean I wouldnt worry about oil in the cooler too much. I would look at changing the seal on the output shaft as well, while its easy to access.

[ccjohnson]

That is the kind of garage I would like to have!

[sopicki]

It's my brother in law's shop. He's got enough room to put 2 semi's with trailers or 4 tractors in it's 90 foot length.....yes I love it too! The shop is usually slow around the holidays hence my chance to get in and start taking things apart (on the other hand their road call business takes off with the cold weather). However, despite everyone in the shop being a diesel mechanic, no one has seen a Detroit fuel pincher or an Allison MT41 :(
Just looking for advice from the people who have been there done that.

[sopicki]

While we had the coach in the air we decided to replace the motor/transmission mounts also. Just like the brakes we had to remove the parts to read numbers off and then try to locate something that would work. The Ford part experts tell me that the mounts have 1961 part numbers and after a week of looking I was not able to locate any exact replacements. We did find some with similar dimensions that I think will end up working better in the long run.46104611This Monday we should have her back on the ground with new transmission mounts, new transmission fluid, new transmission filter, new Timken rear wheel bearings and races, new hub seals and new synthetic gear oil. We're getting there.