I would like to say this is the best board I found. I pretty much found everthing I was looking for on the board by searching but not the axle problem.

Ok, when my dad bought this car about 3-4 years ago the guy said the axle was bad. He was driving it home one day and it started popping and vibrating the car, he said he got home and parked it. Got up the next morning to take it to the shop and the axle problem was gone! The guy at the shop said it popped back in place which happens like 1 in 1 million. Well he gave me the car since i got my lisence, but the popping is back, but it only makes the noise when I back up. Is it something else? I don't think it's the axle, maybe ball joints or bushing i'm not sure, and has this problem happened to anyone before?

My Car: 84 Mercedes 300D TurboDiesel 4-Sedan