Is there anyone on this board who has succesfully fitted a 4L80 into a 4x4? I've got an '02 Avalanche that likes to eat 4L60s.

Would a TH400 with a gear vendor's overdrive be an easier swap?

I really need some help with a long term solution to this problem. My last 60 only went 3,000 miles.

 

Jim has a great write up on the subject on his page.

http://www.neufamily.org/truck.html

It has been done many times now and works great. I was going to do it on my 4x4 but now it's going into the lil truck.

 

What I would really like to know is if there is a way to do it without swapping transfer cases. I wouldn't know where to get my hands on a new transfer case and they can't be cheap.

 

What F8L said.................http://www.neufamily.org/4l80e/4l80swap.html

 

The input gear of the transfer case can be switched to fit the 4l80e. You can also buy a 27T output shaft for the 4l80e to fit the transfer case.