Help with differential problem...

[WannaWagon]

My car has slowly developed a knocking sound from the rear end. At first it was intermittent, and only when accellerating. Now it's all the time on accelleration and when climbing hills. I had my indy mechanic check it out, and he said the differential is failing. Actually, he said the problem is the pinion bearing, but that on these cars it's actually easier to replace the whole diff. They also said it doesn't need to be replaced imminently, that I should just monitor the noise and replace it when it gets real bad.

Well, it sounds pretty darn bad to me already. My wife and I are moving up north in a couple weeks and I'm wondering if I should get it replaced before then for safety's sake.

I've read a little about this problem in the archives here, but wanted to get a second opinion from you guys. Am I really better off replacing the whole diff.? Should I do it right away, or wait?