[angelf0926]

im new to this topic and dont know where to start..i have a 76 monte carlo with a 454..am going to buy a th400 within the next few weeks..and was wondering what differential would be best and which ones would fit? i found three 12 bolt rear ends...one from a c-10 truck, 1970 GTo and another from a 72 Chevelle..would these fit my application?

[RWENUTS]

Here's a chart that should help. You'll need to blow it up a bit to read it better. Measure yours and compare.
Google

[big gear head]

Your '76 Monte Carlo will have the 8.5 corporate rear end. There is nothing wrong with that rear end if you build it right. I recommend a new 30 spline Eaton Pois and a set of Moser 30 spline axles. Moser axles are the only ones that will be a direct fit for the 30 spline upgrade. There are no 12 bolt rear ends that will fit that car. Just build your 8.5 correctly and it will hold up fine. Use the best quality parts that you can get, like name brand gears and a very good installation kit.

[angelf0926]

what about a 10 bolt rear end? i found one that come with 3.31 gears, disk to disk, with break cables, etc...if this is not do able i will take your advice and build mine accordingly

[angelf0926]

sorry i just saw that you mentioned the 8.5" rear end which is a 10 bolt. lol nevermind the question but thank you

[big gear head]

There are several GM 10 bolt rear ends, and the parts from them do not interchange. You have the 8.5, so parts from the 8.2 Chevy, 8.2 BOP and 7.5 rear ends will not fit your 8.5.