They came in the F550s medium dutys from the factory.

There are lots of threads on google... but its not superior to the Ford unit.

https://www.google.com/search?q=swa...Allison+transmission+to+an+05-07+6.0&aqs=chrome..69i57&sourceid=chrome&ie=UTF-8

 

Biggest hurdle is understanding how the 5R100 is far superior. Everyone TALKS about how great the Alison is but its not all that and a bag of potato chips. It has a lot of complaints of overheating, weak input shaft, shift flares and under heavy loads it will put itself in limp mode disabling reverse or anything above 3rd gear.

the 5r100 isn't perfect but its a much better unit for towing, performance or just daily driving, esp when taken care of fluid n filter wise.

 

I agree the Allision is overrated when it's stock but once it's built I'm not sure where to put it. How long till we can swap a 6r140 though?

Get a manual truck or reprogram yours to be a manual then it doesn't care what's behind it.

 

and if you really want to go the allison route.. ( i wouldn't lol) your gonna need a stand - alone TCM that will be able to control the allison.. then you would have to write custom transmission shift points and converter lock-ups so you don't turn that nice new tranny into metal hamburger

 

They came in the F550s medium dutys from the factory.

I've never heard that before. Were they offered as an option to the stock Ford transmission? I have an '07 F550, and I always assumed it had the 5R110...

 

I've heard of them in the F650 and F750s behind a Cummins but never the F550. Should be easy to check either go to Ford and get a build sheet or take a look under the truck the Allision has a spin on filter IIRC.

 

Swapping a 5r110 out for an Allison would be a step backwards. The 5r110 can handle much more than a stock Allison can.

 

Allisons are easily kept cool with a decent trans cooler, just like any other transmission. They don't flare unless the fluid is beyond burnt. The Allison is an EXCELLENT transmission.... once it's built. In the stock form I couldn't care less for it. I have a suncoast trans in my 03 dmax that has 50k miles on it at 500+ rwhp, towing or not it doesn't get a break. Always over 500. It hasn't given me any issues whatsoever since built. They're fairly easy transmissions to swap because they are learning transmissions. I still don't have tcm tuning even with compounds on the truck. Factory transmission tune. When towing I've never seen over 185 degrees with my setup.

However, the STOCK torqshift in my 6.0 sees 600 hp daily, and while it's not happy about it, is holding up great. I know how to treat it, I know what pisses it off, and I go around it. No way in hell would I trade a stock 5R for a stock Allison.

Edit: the stock Allison shafts are good for ~1200 rwhp, they are certainly not weak. They're twice the size of a ford/dodge input shaft. They will NOT limp at stock power. They really only limp when slipped. If the truck is at stock power the Allison will last forever. And actually, a 6 speed Allison would handle the power of a max effort race tune in a 6.0 without hurting it ever, simply cause a 6.0 puts down far less power than a dmax does on just tunes. They just don't have the same fueling capabilities.