Hello, so recently I blew the stock diff in my 1998 Z28. I had bought a used fourth gen diff from a older fourth gen cause there were some differences but I made my own adjustments for conversion and it bolted right in. I have everything set up, but I am trying to attach my stock ls1 aluminum driveshaft, to the new diff. But it feels as if it isn’t mating properly and the brackets aren’t tightening properly. Is there a reason and solution for this? This car is my daily so any help would be appreciated.
the diff is from a lt1 4th gen. Attempting to put in ls1 fourth gen.

 

In my experience the ls1 aluminum driveshaft was plug and play on my 95 Z28 lt1 car.

 

Sounds like the driveshaft u-joint bearing end caps may be too large to fit into the receiver on the pinion shaft. Someone may have changed the driveshaft rear u-joint to a “crossover” type, to accommodate an aftermarket rear axle assembly. Or the driveshaft has a stock u-joint and the replacement rear axle assembly is aftermarket, and the bearing caps are too small.

 

Thanks you guys! I solved the problem I believe by just swapping the yokes

 

The rear yoke is welded to the shaft. The pinion yoke is attached with a large nut, whose torque setting is critical to the pinion bearing preload. What exactly did you swap - the pinion yoke from your blown rear swapped onto the replacement rear?

 

The rear yoke, attached to the pinion , I mean I didn’t torque it too tight , I don’t have any torque tools but I need to be able to drive my car at least to get to the mechanic so they can adjust it.