I wasn't able to use the rear end from the donor 02 Z28 because the spring mounts were just too rusted. I still have the original 85 rear end in with the drum brakes. It seems to be fine but I have been pretty easy on it. I will eventually replace the rear end but haven't decided on which one I want to put in. How much can the 85 rear take before it fails? I just have the stock LS1 and 4L60 out of the 02 with no mods. Thanks

 

They are about the same amount of strength. The 02 rear has more splines on the axles and most likely a nice zexel torsion. I would probably swap the carrier from the 02 and get some 90-92 third gen axles and set up the tirdgen rear end.

 

Having an automatic trans helps extend the life of the rear for sure. Power alone doesn't kill these rears, traction does. The auto helps deliver the power to the rear without the shock loads of a manual trans. Most experts say a 12 bolt is great for an automatic car and the 9" is the way to go for manual. The S60 is another, albeit heavier, good option for an automatic. Your budget will determine the direction you go. The Hawks 8.8 is a really nice piece that would work well for your combo as well. It is a blend between the two and is strong enough for most mild builds.

 

Thanks for the info. Both good ideas. The 8.8 is great but probably out of the budget for now.

 

thats what I did in my '87