[jesse james begyn]

I can buy a complete 6 speed allison with shifter and tcm out of a wrecked truck and I would like to put a suncoast iv in it rather than spending $1800 for thier 6 speed upgrade for my 5 speed ally. Is this doable. thanks

 

[gtmax]

I guess in theory it's do-able, but in reality there's probably some wiring problems that will come into play--it can't be that easy.

I think you'd spend more money buying the wrecked stuff, updating it to Suncoast IV status; rather than just updating your present 5 speed along with the 6 speed conversion. This would also require less fabrication and headaches.

 

[Kappa9012]

Yeah the logistics of making that work would be a nightmare!

 

[Cougar281]

The Short answer is No.

The longer answer is maybe, if you have access to TCM programming that pretty much no one outside Allison has, which brings us back to the short answer: No.