Agh, my rear end is still clunking.

[Patrick Sullivan]

I get a definate clunk/jerk sometimes when I'm shifting from park into drive or reverse. I don't get it always, usually when I have pulled forward into a parking space and I then go to back out. Seems like something is binding up or has too much free play in my drivetrain. Thing is, the tranny, u-joints and carrier bearing are new. That leaves my rear differential..

It's an HO52 rear end with an HO72 3rd member. I imagine it's just worn out.. (Whatever the previous owner did to burn up the tranny in 40,000 miles probably damaged the diff, too). How do I go about replacing the gears in these things? Is it something I should even attempt? Or should I just bring it down to the shop? Can you even get new spiders for these things? How about posi units? Should I just replace the whole 3rd member? Have I asked enough questions? :p

Thanks.