I have a set of GM Original gears for 10 bolt 8.5

very good condition

85.00

13.00 shipping

Thank you, Jim
J D
AKRON, OH

 

It's been said that the inners of the 12 bolt is actually the same as the 10 bolt. Do you know if this is true? Would these be the same size? I'm looking for 3.73 for my 12 bolt posi.

 

Whom ever told you this was wrong. The Type O 12 bolt & the 8.5" ten bolt share nothing more than the fluid you put in them.


There are no 3.73 gears for a Type O 12 bolt. There are for a Type C 12 bolt.


So, are you asking about at Type O or Type C rear diff?

 

I believe that what I have is a 12 bolt type O posi rear. They don't make 3.73 gears that would fit in there? That sounds a bit strange. Why would that be? I would assume they'd make every gear for every rear. Certainly I couldn't be the first to want these gears in a 12 bolt type O

 

The only gear ratios close to what you desire are 3.42 & 3.91. There are no 3.73s. Never have been & likely never will be. Get used to it.


You need to use the search button & do some research on the type O. You need a specific carrier to run specific gear sets. Talk to Jim (original poster) he can hook you up with what you need.