Re: Allison 545 to Allison 1000 series? possible or not?
It can be done. It is expensive. It would make the vehicle perform much better, if you're willing to invest five grand or more. The hard part is finding a shop that can find the parts and knows how to do the job right.
Replacing an AT in a motorhome, or replacing the transmission in a pickup truck with an Allison are questions that get asked quite often. It's the cost of the job that usually prevents it from getting done. Industrial Automatic Transmission Service (division of Inland Truck Parts) in Irving, TX used to have a deal where they replaced the AT in a motorhome with an MT more cost effectively than putting in the 1000 and you got most of the benefits for a much better price.