I have a new body style '99 silverado, 10 bolt 2wd...someone told me that some of the 99's still had the 8.5" in them with the, I belive, 28 spline axles...I'm going to be buyin an Eaton LSD soon and need to know for sure what I have. Can I pull this info out of the VIN or would pullin the diff cover tell me anything, I would assume that counting splines would be somewhat difficult and I dont really wana pull the cover, check it then put it back on and in a week have to do it again. Please let me know!

 

Anything 89 and later has 30 spline axles. All the 99 trucks had the 8.6 that I have ever run across. The only difference is the bearing hub diameter on the diff case, ring and pinion is the same. The Eaton is the same for 89-up because they have the larger hub diameter already so it would work for you. 19559-010. and a 8.6 bearing kit.

 

just to be certain can I get a second opinion please......

 

it's 8.6

 

Like I said, it wouldnt matter anyway if it was a 8.6, the 30 spline 8.5 would use the same Eaton anyway. The only 99's that have ever been reported to have a 8.5 are the Suburban/Tahoe, all the NBS trucks had the 8.6.

 

yup, I was worried about the same thing before I did mine. Dont worrie it will work.

 

When I ordered my Eaton, from Eaton, they told me 8.5 and 8.6 were the same kit. Did you get gears to go with it?