Front end vibration shimmy shake wobble

[badgator]

My 85 300sd started to slightly pull to the right(front pass wheel) about a month ago, I bought it about 2-3 months ago. It pulled progessively harder and started vibrating from 65-70 mph. You could raise/lower speed to eliminate the vibration, for a couple weeks. Last weekend I drove about 90 mi, up to 80 mph - to eliminate the vibration, it started pulling a lot harder to the right, like a flat tire. Since I bought it, tire pressure is constantly even at 30-35 psi. In the last 10 mi before I got home, it felt like the lug bolts were loose, not the case (very violent shaking down to 10 mph). I installed the early model spare - the bolts are too short for it, I have late model rims. Installed idler arm kit this morning, AND Bought a nice wheel/michelin tire at upullit as I needed a spare anyhow. as there was a huge ply separation on old passenger tire. Now it still shakes but not nearly as bad, front end seems tight now - tie rod ends, center link, probably try steering damper next. Any ideas?

[badgator]

Didn't drive with early model spare.

[rrgrassi]

Check the wheel bearings as well. Also check for sticking caliper. Check all the suspension joints, and all bushings. Check the guide rods also.

[patbob]

You said the ply separated on the front passenger tire. Could it have also happened to the one on the drivers side?

Maybe go back to upullit and get the other tire and try the pair on the front? If you get it already mounted like the last, you can save the mount/balance effort and then you're only an extra rim away from a set for snows.

I'm no front end expert, but I can't see anything that appears to be tight to be causing a vibration. It would have to be very, very loose to vibrate, especially at low speeds.

[gwooden]

I experienced something very similar, turned out to be outer tie rod.

-graham

[FRANKNBENZ]

First simple test I always do after driving for a while is to place my hand on the wheel hub to see if it is hot or if it is black with grease. That is the first indication of possible trouble.

Assuming tire pressure is OK, ensure all your tires match for size. Mixed brands could be the culprit.

Inspect wear patterns.

Pulling right could be caused by lots of stuff. Some ideas:

Get the wheel up off the pavement and in space (not on a ramp) so that you can try to spin it. For safety only do this on level pavement (not asphalt in the hot sun) and use a jack stand.

1. If it spins freely, listen and feel carefully for any intermittent scraping noise and or slowing of the wheel spin at one spot. This might mean the rotor is warped.

2. If it does not spin freely, the caliper might be binding. Replace caliper. If so, replace all pads in the front, not just on one wheel.

3. Grab the wheel at the 12 and 6 o'clock positions and try to alternately push top / pull bottom and vv. If there is movement or clicking, the wheel bearing will need inspection and adjustment and or replacement (again, replace like items on both the drive and passenger sides).

4. Grab the wheel at 9 and 3 with someone holding the steering wheel and push pull as above. This is a basic but not complete test for all the tie rod stuff at least on that end.

5. Turn the steering wheel so that the wheel in question is completely over to the stop. You should be able to see the caliper, brake hose, sensor cable, etc. Grab the outer tie rod frimly (see photo in FastLane Parts) and see if you can rotate it. If it moves freely or has wet goo coming out of either boot, change it (again, change out the other side as well). Note torque specs for the connecting and adjusting nuts.

6. Hunker down and look at the center tie rod (again, FastLane photo; aka "drag lilnk"); do the firm rotate test and check for greasy goo -- remember, only one side may be "bad". There is only one of these.

NOTE: Good advice from Forum Folks recommend that if you are going to swap out any steering tie rod element, and your records show this has not been done recently, no accidents, etc., replace all four components: L/R outer tie rods, center tie rod (aka drag link) and the steering damper. All these parts should run around $150 or less. See threads on How To DIY.

While you are under there check out the upper and lower ball joints, again for goo oozing out, movement, etc. Threads cover R & R with tool tips.

Finally, if any steering work is executed, it is important that a 4-wheel alignment be done to bring the work back into specs and provide safe control of the vehicle.

Good luck.

[zill]

New tires and sterring damper

[zill]

Sorry,

New tires and install new stearing damper.

Zill

[85chedeng300D]

I had similar problems before but not on MB, it was from a Mitsubishi Galant.
The car will always pull to the right then I tried swapping both left and right front tires and the car started pulling to the left, I ended up replacing with new tires and solved the problem, I don't know how and why.....? You can try for troubleshooting purposes.

[badgator]

Sigma Regent tires are junk, a 14 in size was recalled, not my 205-65-15 rear ones also feel bad. Have a nice pair of Michelins on front, what a difference!

[badgator]

Replaced ANOTHER tire now, makes it both front AND rr tires with bad ply separations. I can already feel the lr tire is next. Major quality problems with these tires make by Cooper tire! Tires came on my 300sd I bought a couple months ago, previous owner died, one of the few receipts I don't have is for the tires. Basically the tires work fine then a vibration starts and quickly gets worse over a couple days. Good faith replacement? I don't think I want them on any car I own!

[badgator]

Well the last of the 4 Sigma Regent 205-65-15 (35 psi) expired. Driving 65 mph it went from minor vibration to major in about 5 miles, then smack (tread slapping on pavement). The tread separated about 1/3 of the way around the tire. Guess the tires can't take 95 degree heat AND high speeds - 70 mph!