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79' 300D loud clunking/rattling from rear end on right turns

Submitted by waldos313 on 11 July 2008 - 12:08pm.
My 1979 300D started making a very loud and concerning metal on metal rattle about two days ago on my home. I didn't do anything to warrant it either, it just started around a 90 degree right turn at about 15 mph. Now, it makes the sound which comes equally from both sides every time I turn right at greater than 5 mph and progressively gets faster with speed. It is definitely a rotational sound too. I thought initially it was the exhaust contacting the driveshaft so I re-hung the exhaust with some beefy c-clamps but that wasn't it and I see no wear marks anywhere on the driveshaft, on the coupling to the rear end or to both wheels. The sound is also there to a much lesser extent going over bumps. Any ideas?? Thanks, Brandon
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Suspect one or both of your rear axles

11 July 2008 - 10:37pm
Kent Bergsma
Hi Brandon, I could be wrong but this sound very much like one or more of you rear axle spider joints have gone bad. Kent

1982 300D low speed 3rd gear clunk

11 July 2008 - 11:29pm
300dster
When driving at 25 or 30 mph there is a loud clunk when the tranny shifts into 3rd gear and also when it down shifts. It feels and sounds more like the rear end and not the tranny but I'm not postive.I've read that this is caused by worn u-joints.I checked them along with the flex disk and they appear to fine. I would like to resolve this issue and prevent further damage if possible. Any suggestions? Thank you, Anthony

1979 300D

12 July 2008 - 5:33am
waldos313
Thanks for the reply Kent. Is there a way I can be sure? I see you have a kit to do this myself. What level of difficulty would you say this is? My wife and I love working on these cars but sometimes we just don't have the time. There is a reputable import shop near us as well. Thanks again, Brandon 1979 300D "Red" 1985 300D Turbo "Blue"

sway bar

15 July 2008 - 10:17am
waldos313
The noise was actually the sway bar connection on the right side. The plastic coupling had failed and the sway bar was contacting the driveshaft when I would make right turns. Weird!! Thanks, Brandon 1979 300D "Red" 1985 300D Turbo "Blue"