Rear End Thump
Thread Starter
Member
Joined: Nov 2004
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
Rear End Thump
Hi, i just bought a 1986 300E and i noticed that when i am coming to a stop and the transmission is switching from 3 to 2 i get a rather loud Clunk noise. what may be causing this? it happens all the time. i also get this noise when switching from reverse to drive. and visa-versa.
Thanks In Advance.
-Nick
Thanks In Advance.
-Nick
Senior Member
Joined: Aug 2004
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From: Richmond, Va.
1991 300E
could be your flex disc on the propeller shaft. When they are worn out they don't take all the slack out of a hard shift. You will notice a delayed "thump" when putting the car in drive right after start up. If they get really bad they can unravel and wrap around the drive shaft like a shredded golf ball. I don't think they're too hard to replace. Can't remember if there is one or two of them though.
Out Of Control!!
Joined: Feb 2003
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haters crazy
There are 2 flex discs. Another thing you want to look at are the differential bushings. I had to replace both of these on mine. Diffeential bushings are more difficult to change than flex disks.
Thread Starter
Member
Joined: Nov 2004
Posts: 123
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
about how much will this cost me? is it something i can do myself? is it easy to get at? this is my first mercedes and first car all together. so if i can do it myself that would be great.
Out Of Control!!
Joined: Feb 2003
Posts: 13,489
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haters crazy
It depends on how mechanically inclined you are. The differential bushings pretty much require a lift and you have to pull the differential so its pretty hard. The flex discs are easier but if you dont have much mechanical experience I wouldnt try it. I have no idea how much this would cost to get done at a shop but parts shouldnt be over a hundred dollars.
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Joined: Feb 2002
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From: Chicago
90 300e and B5 S4
Im about to change the front flex disc on my 90 300e (lots of freeplay of the front flex disc). If you go underneath the car (in park, lifted up) you can move the driveshaft by hand to recreate the thump sound. Look at the flex discs and notice how much bigger the holes might have gotten over time.
Thread Starter
Member
Joined: Nov 2004
Posts: 123
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From: Modesto, CA
1992 400E (86 300E, 98 S420) - Retired
thanks alot to everyone who replied. got under my car and there was barley any rubber left. moved the drive-shaft with my hand and recreated the noise. i bought this car used and it has 215500 miles on it. is there any chance that there was damage caused by this?
-Nick
-Nick
