OK. I need some help here. Are you out there Wanna Diesel??? I have an opportunity to purchase an Allison AT545RM that was in a 1992 school bus. My question is will this fit into our trucks? As you see in my sig. i have an 85 D-350 crewcab. Has anyone heard of this being done? A quick reply will be appreciated due to the fact i'm trying to get my truck ready for a family camping trip in july and i want to get this done and out of the way.

 

1stgen545 actually did that swap in his 4wd. He had to do a bodylift, as the transmission was too big to fit in the tunnel I believe.

 

I actually did some research on the Allison transmission before I installed the 47RH in my 1st gen since I was always hauling heavy. What I was told by several transmission shops was that although Allison had a very good reputation for building good heavy duty transmissions, the one that would fit behind the 5.9 Cummins from the school busses( I can't remember the model now) were not as goos as the other Allison transmissions. What I was told be many shops was that it was very costly to put an Allison in our trucks and that if you were to sink the same amount of money in a 47RH you would actually have a better transmission. They said that in stock form the Allison was better, but the 47RH could be made to hold up better than that particular model of Allison for the same amount of money. I am no transmission expert by any means, but I was told the same thing by more than one transmission man and they convinced me to spend my money on the 47RH.

 

I know 1stgen545 has quite a bit of power in his truck, and does sledpull with it no problem. He does have it beefed up though.

 

Better check the final drive ratio on that Allison. Likely one of the reasons the 47RH was/is recommended.

 

AFAIK the 545 is not an overdrive trans.

 

Correct... (I had access to 2 of them from the same source a year ago )

 

Thanks guys,i have since done some more research and discovered this trans will not do what i am looking to get done. I talked to the shop at Covington Allison in Greenboro,N.C and i was told it will work but body mod's would need to be done. I am trying to get an updated trans into my truck with the least amount of work involved. Soooooooo.... i guess there is no reason to continue this thread. Thanks for all the input Augie Dog