4.3 set in my 4L60E


Active Member
Jun 1, 2001
Put 4.3 gears from a 2 wheel drive in my 4 x 4 case.
Acts like it is trying to keep 1st engaged at same time I select R.
Getting metal in the pan.
Tried both valve bodies - no change.
Is this a feasible conversion?
I'd like the lower 1st gear since changing my rear from 4.56 to 3.73.
I found the issue.
The builder somehow got the reverse drum out of alignment - destroyed the case.
Rebuilding it myself.
I'm no expert, however, I'm informed different ratio gearsets are available for the 4L60E & pulling the 4.56 for a 3.73 made a lower 1st gear look better.
I have never ever scene Stock GM gears that are different in the 700/60/65s. The only big difference in a 65 is the 5 Pinion planetary sets. I have built tons of these trans and have never put a reverse drum "Out of alignment" or scene anyone else do it... What do you mean by "out of alignment"?