My guess is the Allison tranny not fitting. Imagine hooking that burban up to that 7 ton trailer and pulling it (and the family, the luggage, the dog, the groceries, plus all the holiday gifts for Uncle Bill and family) across the country. I'd bet the D-max would be up for the job, but I seriously have questions about the old trannies.

I don't know much about the new one. But that's my guess...http://www.thedieselpageforums.com/t...ons/icon10.gif
Talking