w123 bad rear end TWITCH - Page 2 - PeachParts Mercedes-Benz Forum

Zacharias · #16 08-01-2011, 07:52 PM

Tire wear is perfectly even. Rear end sits up like a new car. Very little squat even on acceleration.

boneheaddoctor · #17 08-01-2011, 09:41 PM

Quote:

Originally Posted by Zacharias

Tires have perfect tread wear all around. Rear end sits up like a newish car.

Shocks don't support the rear end. not on the coupes or sedans anyway. The TD's are to a degree but not exclusively.

boneheaddoctor · #18 08-01-2011, 09:41 PM

Quote:

Originally Posted by Zacharias

Tires have perfect tread wear all around. Rear end sits up like a newish car.

Shocks don't support the rear end. not on the coupes or sedans anyway. The TD's are to a degree (actually the accumulators) but still not exclusively.

scottmcphee · #19 08-01-2011, 09:59 PM

Check the toe-in of each wheel. Too much toe in at the rear will shift the car wickedly when uneven pavement traction is encountered between the two rear tires..

Park the car on flat level ground, steering wheel pointed dead ahead. Run a string along one side of the car at center hub height (center of the Mercedes star on the hub) so the string is the same distance away from each hub. An inch away is fine, it doesn't matter exactly how much, just that it is exactly the same front and back. When that's set, measure the string-to-rim distance at the leading edge and trailing edge of each wheel, one at a time. If there's a difference of the rim distances at one wheel then that wheel has toe in or toe out. The fronts should be zero toe. The rears can have a little toe in. Like 1/8" difference.

When I replace tie-rods, I use this method to set zero toe at front. No need to go to alignment shop for this!

t walgamuth · #20 08-01-2011, 10:49 PM

If the shocks are completely gone, again, I have had this happen on KYB and on Ranchos which are built by Kyb, when the car hits small bumps like certain types of rain grooves the rear will just take off sideways. It did it on my big dodge at the front too.....and they will go bad pretty much all at once.

Oh And there is no adjustment for toe on the rear of a benz....at least a 123.

Stretch · #21 08-02-2011, 05:00 AM

Quote:

Originally Posted by t walgamuth

If the shocks are completely gone, again, I have had this happen on KYB and on Ranchos which are built by Kyb, when the car hits small bumps like certain types of rain grooves the rear will just take off sideways. It did it on my big dodge at the front too.....and they will go bad pretty much all at once.

Oh And there is no adjustment for toe on the rear of a benz....at least a 123.

True for a standard set up but Fastlane actually sell eccentric trailing arm bushings I learnt recently. I think Winmut (sorry for the spelling it is probably wrong) was looking into them not so long ago

Stretch · #22 08-02-2011, 05:07 AM

If it is a problem with the back end - have you checked if there is any play in the axles? Jack up rear end and pull up and down on the wheel...

Pretty unlikely as when worn they tend to be noisy... I'm just thinking along the lines of something that could provoke such an extreme reaction over a bumpy road where the weight of the car "felt" at the wheels varies so much.