I thought that the front drive shaft didn't spin unless it's in 4wd. Am I wrong?
I had the drive shaft balanced because my company mech (he's seems fairly competant at working on cranes and rebuilding diesels, but this shook my confidence) pulled it and removed the front U-joint and played around with the slip yoke. While getting the ujoint out, he broke the cast iron damper ring off the slip yoke. Then it started vibrating at about 60mph. WHen I had my wife take it to the only place in frikken Birmingham, AL that balances drive shafts, they said the front U-joint was shot. They replaced it for $15 and balanced the shaft for $40. When I got it back, it still kinda vibrates, but not as bad, and seems to only do it in deceleration between 70 and 60mph. I assumed that they didn't replace the rear U-joint cause it didn't need it. I havent seen any slack in it.
I feel like the clunk is coming from between the transfer case and the rear tires. When I'm in 4wd, the sound is gone. It only happens in 2wd.
Tons of fresh grease in the slip yoke that slides into the transfer case seems to help, but not totally eliminate the noise for about 10 miles.
It's starting to clunk now when I take off from a dead stop. Not every time, but fairly often. When I say dead stop, I mean a red light, where I never take it out of drive.