Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help

Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

LinkBack Thread Tools Display Modes
Old 01-24-2000, 04:26 PM
Posts: n/a
Allright, let's see what we come up with. We drove from Florida up the Alaskan Highway in my 83 300TDT this summer, no problem other than an annoying metallic thumping problem from the rear driver side. When I checked the rear end the passenger side half shaft had leaked all the fluid so i replaced it on the road with an after market halfshaft, I actually replaced both sides for safety. On return trip back to Florida the sound began to reoccur. Everything I have seen published say either Wheel Bearings or Pinion Gear. The sound goes with the rotation of tire, is metallic, but is not always present. Could it be the U-Joint hitting the frame from an overloaded vehicle? Or is it the rear wheel bearing, which I shoul have replaced when I did the halfshaft. Or is it the U joint, which has no significant play in it. Ideas, comments?????
Reply With Quote
Old 01-24-2000, 06:54 PM
Registered User
Join Date: Jan 2000
Location: New Bedford, MA USA
Posts: 1,583
Rear wheel bearings generally get noisy (hum or if really getting bad, growl. Thumping is not characteristic of a bearing, although, I suppose anything is possible. Pinion is not likely as it is usually turning 3 to 4 times faster than the wheels (depends on final drive ratio) and failure mode for that component is generally a pronounced whine or hum. (check backlash). If you have any rubber coupling discs in that rear end, they would be suspect. If you have replaced both half shafts, then I would look at the rear end suspension components. Possibly the carrier bushings and any other locating components in the rear end. U-joints should never normally make contact with the frame as the nest (center section) is bolted to the frame. Start at the outermost parts of the suspension and work inward. You have more than one u-joint in that car. With independent rear suspension, there are at least 5 variable geometry drive components you should check, be they u joints, cv joints or rubber couplings. Depends on car and model. A rythmic metallic thumping sound like something worn or out of balance. Hope this helps...

Jeff L
1987 300e
1989 300e

[This message has been edited by jeffsr (edited 01-24-2000).]
Reply With Quote
Old 01-24-2000, 09:19 PM
Registered User
Join Date: Mar 1999
Location: Suwanee, GA, USA
Posts: 4,712
How about a bubble in one of the belts of the tires? I have seen this more than once.

1981 280GE SWB
1987 16V

Reply With Quote
Old 01-24-2000, 10:00 PM
Posts: n/a
Actually, the tires have been replaced so I'm going to try looking into the variable geometry parts that Jeff mentioned instead of the bearings. May be a flex disc or such. I will try raising the rear suspension manually by adjusting the hydraulic suspension linkage to see if the sound goes away if I raise the vehicle. If it does, it must be drive axle related instead of bearings. What do you think Benzmac.
Reply With Quote
Old 01-25-2000, 10:50 PM
Registered User
Join Date: Jun 1999
Location: Los Angeles, Calif, USA
Posts: 521
Could it be the parking brake?

Reply With Quote
Old 01-26-2000, 09:21 PM
Registered User
Join Date: Sep 1999
Location: montreal,quebec,canada
Posts: 53
actually i had the same problem....found to be the parking brake springs.renew the parking brake with the springs ....should do the trick
Reply With Quote
Old 01-26-2000, 10:12 PM
Nick Jamal
Posts: n/a
I have to say, the parking brake springs in my car drove me nuts till I figured out where the noise was coming from...
Reply With Quote


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

Similar Threads
Thread Thread Starter Forum Replies Last Post
Mysterous thumping sound no one can repair! Matt201 Tech Help 3 03-13-2001 01:31 PM
Knocking or Thumping sound. Help! mkcos Tech Help 5 12-02-2000 09:43 PM
Rear thumping noise on 300TDT SteveB Tech Help 1 09-08-1999 05:29 PM
Thumping Sound on 99' C280 FSP Tech Help 1 04-01-1999 10:21 PM

All times are GMT -4. The time now is 11:07 AM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2018, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2018 Pelican Parts LLC - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page