First post on this forum, but certain not to be the last. I recently bought a 1979 450 SL with only 50,000 miles on it. I have a few things to attend to and the most immediate I discovered last night. Under hard acceleration I have a series of "clunking" sounds that sound like it is coming from the axle/drive line. As I drive more reserved I do not hear or feel it. Any suggestions about where to start?

Check the drive-line center bushing. It consists of a bearing supported in a rubber saddle. The rubber dry rots allowing the drive-line to move. Most noticeable in a hard acceleration.

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Mike, Thanks for the reply. I will get it on stands today and look.

Ok, this is admission of ignorance admission. It was on the lift today and both the mechanic and I looked and thought it looked OK. So just what is it I am looking for? Should I be able to detect a problem visually or does it require some disassembly to see if it has deteriorated? I have the tools, I have the motivation, I don't have the most important part-knowledge.

I would say you should suspect an axle shaft to be the problem. Those axle shafts have a "CV" joint at each end, so that means you have four of them. If they are really used and abused and the rubber boots are cracked and all the grease has leaked out, they will start making a lot of noise. If they are "rebuilt" axles, they can look OK, but again they can be the cause of a lot of clunking. New ones right now are not expensive and any DIY mechanic change change them both out in 2 to 3 hours.

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1983 Mercedes W123 240D 4 Speed 285,000 on the road with a 617 turbo, beautiful butter yellow, license plate # 83 240D INDIANA

2003 Jaguar Type X, AWD. beautiful, good mileage,
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I appreciate your comments. I just took it into a local repair shop and have a potential $1700.00 repair bill for undercarriage mounts and the mid driveshaft bearing replacement. I am very unhappy with the dealer I bought it from as it made this sound prior to purchase and they told me they examined it on the lift and found nothing wrong. I am going back today with the quote to see if I can get them to either pay at least for the parts, or will take the car back. Sad as the car seems to be mostly intact and such low mileage.