I will be swapping out my AX15 this winter (my synchro's are shot). I have heard good things about the rebuilt tranny's on eBay where you send back your core.
Anyway, I currently have the 4.2 but I'm only a few years away from rebuilding or replacing that too. And once the time comes, I've been considering just swapping it with a rebuilt 4.0. (Haven't decided on that yet).
My question... If I put in the AX15 now on the 4.2, what challenges am I adding down the road when the time comes to put in the 4.0? I'm sure it's not much, but wanted to ask. I dont want to handcuff myself to the 4.2.
Replacing both the trans and the block together is financially out of the question.