Has anyone done one of these conversions? I understand that with a Ford adapter ring, at least a Allison AT 545 or MT 643 will fit. My understanding, 370, 429, & 460 all have the same bellhousing pattern
I have done several re/re on 370 equiped ford trucks with the allison tranny, and the adapter is very big and heavy, also the motor mounts are part of the adapter as the tranny just hangs of the back of the adapter with only a small cross member above the tranny for support.The timing cover is also cast iron and has another perc casted into the bottom of it for the front motor mount. I have looked at this set up for a f350 car hauler I am partner in, and If these pieces where made avalible I would try to fit them in the f350.
Is this what you are thinking to adapt the allison to light duty application Eric
Looking into options for getting more gears than my C6 has and something that will stand up to at least 750 Lb-Ft as that is a little over the target for my turbo 460 build.
Anyone know how a 545 would respond to higher power levels/RPM?
The Allison AT545 are light duty "medium truck" transmissions at best. They were built to a price point, and as such have very limited specifications. None of them were even close to being rated for 750 ft lbs of torque. Again this was the "economy" model of Allison's. They tend to fail on a all to regular basis as they are "price point" transmissions, which many overlook when specking the truck origionaly, then complain about the crappy transmission, when in all fault it was a misapplication for that particular service / truck.
The MT640/650 series are closer to what you want, and they range in torque handling from about 550 to 700 ft lbs depending upon the model.
None are rated for more than 4000 rpm input. Most are rated at a maximum input rpm of 3000. No, there are no shift kits nor anything that can be done to raise the rated rpm level readily available. In fact I do not think that anyone ever did much with these as far as performance. They are big heavy medium truck transmissions with a significant amount of heavy rotating mass that are designed to operate within a certain operating range with a minimum amount of failure.
Now newer electronic Allison's might have some aftermarket support for mods, but just buying into the basic transmission / controller is going to set you back some $$ plus any custom work. I have done absolutely nothing with these newer Allison's, my experience is the fully mechanical units.
Thank you for the information. I have only heard (read) so far that these transmissions will physically work, never anything about them.
Looks like building an E4OD and running a stand alone controller is my only realistic option to stay with an automatic, too bad it's such an expensive option.
It was a good thought, but while good transmissions, the mechanical Allison's are generally big heavy beasts better suited to lower rpm ranges.
As to the E4OD I actually have had good luck with then and there is all sorts of aftermarket support for them. That is probably the direction I would go as it is just easier because of the fit and parts / mod support.
As another thought, I wonder how the Allison behind the Duramax would work? I know there is some aftermarket support for them. but they are not something that I have ever worked on, as they are newer. I also have zero idea if they use a integral bell housing or the SAE pattern with a adapter like the older Allison's.
Of course the Allison "world" transmissions are not cheap either....