Im looking for a locker for the rear of my truck and need to know if it is the 8.8 or 9.75 size axle. I want to say its the 8.8 but vin decoding doesnt tell me, and the axle codes that I found by doing a search here only told me the gear ratio. Its a 2004 STX 4.6 4x4 reg cab. Im looking at a 8.8 28 spline eaton elocker right now. Problems?

 

hmmm I believe you have the 8.8 31spline. I dont think they put the 9.75 in the new bodies I think its the 10.25. But not to sure about that though.