Stoke

I recently bought a 70 coupe that had been sitting in a field for several years. The motor is shot (threw a rod), the transmission (C4) looks fairly clean, and it has an 8" rear end (unknown gears). As I start going through this car to get it back on the road I'm going to go through the transmission with a kit prior to installing the engine. My question is, not really having any history on the car what should I do to the rear end to ensure that it is not damaged? I have moved the car and it rolls easy and doesn't make any noise but the fluid in the differential has got to be 20 years old at least. I'm going to replace the rear suspension on the car and while I have the rear end housing loose from the springs I would like to take care of any issues with it. I have no experience working on differentials and any advice would be greatly appreciated.

67mustang302

You can pull the 3rd member and visually inspect it, otherwise I'd just change the fluid and drive it till it breaks.