I want to install 3.73 gears in my 06 but i cant find any anywhere. I was told by my parts department that in 06 they went to a 8.6 ring gear instead of the 8.5. Where can i find gears without buying the $800 GM gears?

 

Randy's ring and pinion?

 

8.5 is the same as the 8.6

 

The difference is not in the ring gear but in the carrier bearings.

 

They have called them the 8.6 since 2000 or so. The carrier bearings are different for some reason. I put a 2000 model G80 in my 95 1500. I had to go to the part store with a pair of calipers and dig through the bearing dimension book to get some that worked. I used a set of 1970 something model used 8.5 2.73 gears on the 2000 model G80.

 

so just dont worry about it and buy the 8.5 set???

 

yes the older year model gears will work fine!!!

 

I just put a set of 3:90's, 8.5 in my 06, and a set of 3:73, 8.5's in my friend's 06 and had no problems at all. We didn't change any of the bearings out, just changed gears, pressed off old bearings and reused since both trucks had less than 1500 miles on them. Do it and don't be sceered

 

which do you like better for the trucks 3.73 or the 3.90s???

 

4.10's