<img src="/forums/images/graemlins/confused.gif" alt="" />I was looking on the net for master bearing kits for 8" 4.56 and 7.5" 4.56 ring and pinion install.I believe it was on Randy's R&P and Precision Gear that they showed 2 different sizes for the 8" rear.By the way,this is a 22re,5-speed with stock 4.10's.OK,back to the ??'s.They show an 8"(A) 1-1/2 diameter,8"(B) 1-5/8 diameter.I'm guessing this is the pinion shaft size.The 7.5 front only had 1 listing but it didn't say what the diameter was.What size should go into the 4 cyl and why are there 2 different sizes?The reason I'm asking is because I'm buying front and rear 4.56 ring and pinion from a private party.Thanks for any help! <img src="/forums/images/graemlins/cheers.gif" alt="" />

The 1.5" pinion(length of the pinion head) is for 79~85 trucks.....the 1.625" pinion is for 86~95ish trucks....your 87 wants that one. <img src="/forums/images/graemlins/cheers.gif" alt="" />

another thing.....the long pinion head(1.625") is usually more money and harder to find.....there is nothing wrong with using the short pinion head in your 87 with a larger pinion shim pack(~.240").....I would.

<img src="/forums/images/graemlins/kewl.gif" alt="" />Thanks Zuk,that's what I needed to know! <img src="/forums/images/graemlins/cheers.gif" alt="" />