I'm doing an axle swap on my Tahoe, and need to replace the rear U-Joint on the driveshaft. When I pull the driveshaft out, the little rubber dust boot on the T-case output has a lil weephole and leaks a little bit. I didn't want to see if it would constantly leak, or just leak a little, what's left in there. Does anyone know for sure before I go pull the driveshaft and drain my T-Case? The T-Case is a slip-yoke design, NP-241 I think. It's a 1997 Chevrolet Tahoe, 4 door if that makes a difference.

Thanks guys!
Travis

When you pull the driveshaft out it is going to leak all over the ground, unless you drane the t-case first.

When you pull the driveshaft out it is going to leak all over the ground, unless you drane the t-case first.


Um, no. The fluid level in the t-case is well below the rear output unless the tranny has been leaking fluid into the t-case. The slip yokes do leak a little bit all of the time since the yoke does not just rotate in the seal but it slips in and out also.

Wanted to confirm what Black Dog said. I pulled the shaft and it dribbled a bit, but it didn't drain the T-case. Just caught the oil, and it was done dripping within 10 seconds.

pull it out and tap in a new one, 10minute if you suck.

BTW, ATF (GM Dextron III, etc) is the recommended lubricant for the NP-241. After you get done replacing the U-joint, check the slip yoke for nicks and burrs before you stick it back in, a quick buff with some super-uber-fine scotchbrite or emery cloth, and a little dab of grease to lube the seal should help keep the output seal from leaking. It's good idea to replace the rear output seal them every few years anyway, so it might be agoodidea to replace it while you have the driveshaft out.