Hello all. Here's what's going on. About a month ago I had a rear pinion seal go bad on me and I had it replaced. When the car was taken for a test run from the shop, it made this horrible squeal when I started to accelerate then it went away after about a 1/4 of a mile. When I mentioned this to the mechanic he said it could have been the new seal wearing in so I didn't think anything of it. Well on the way home I heard it again. Anyway, this is what it does. Initially, I'll hear a groan noise then it is followed by the squeaking. The strange part is the squeaking isn't constant. When it's squeaking, it'll squeak for about 1-2 seconds, pause for about a 1/2 second, squeak for another 1-2 seconds an so fourth. The squeaking will go away after driving for about a mile at 50mph. I've read a few other posts about squeaking noises but their noises are more constant. This is on a 98GT 8.8 Diff with 3.73 gears. Any ideas?