I have read that if you go with the 4.56 gears you have to grind out the diff cover or something? Is that correct? What gears fit without having to mod?

Has anyone used 4.11s?

 

I haven't seen any posts about needing to grind the diff cover. I'm planning to go with 4.11's because I drive like 80% highway, and don't want to be layin' down 2400 RPMS when I'm cruising at highway speeds.

 

i would imagine that grinding down the diff cover would be for a locker of some sort. all thats replaced when re gearing is the ring and pinion.

 

Some carriers require a grinding of the carrier when going to a different gears. I think it was either the old Broncos or Blazers needed it. One carrier was good from like 3.xx - 4.11 and one from 4.11 up. It's not an issue with our trucks at all...