Here's what I've done. Track rod bushings, left and right tie rods, and lower ball joints on both side. Idler arm bushing. I jack up the passenger front end. There is still a little play in the steering setup. I can still wiggle the wheel in the 9 and 3 o'clock, but not the 6 and 12 o'clock position. This doesn't occur in the driver side. The steering shock still is good, center tie rod appears good.

I have thought of wheel bearing, but wouln't the wheel wiggle in all position. It looks like the steering set up has play in it. Should I replace the steering shock and center tie rod? I'm not optimistic that it will solve the situation. Any thoughts?

Thanks,

John

You need to find out where the play is occuring. Check each component while someone wiggles the wheel. It should be easy to find where the loose part is. Check the steering box.

__________________
I got too many cars!! Insurance eats me alive. Dave

78 Corvette Stingray - 3k
82 242 Turbo Volvo - Manual - 270k
86 300e 5 speed manual - 210k
87 420sel - 240k
89 560sl - 78k
91 420sel - 205k
91 560sel - 85k
94 GMC Suburban - 90k
97 Harley Davidson Heritage Softail - 25k
00 GMC Silverado 1 ton 30k

you've done everything else it has to be the right side ball joint on the drag link.

__________________
David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
http://www.w108.org/gallery/albums/A...1159.thumb.jpg

I would start by having the tyres balanced.
126’s are very sensitive, a slight unbalance will make your front end vibrate.

The steering shock can certainly be the culprit, but, you mentioned that you believe that it's OK? Is it still original.........how did you confirm that it's OK?

Unbalance in the tires and any out of round condition in the tires will definitely cause vibration on a W126. In fact, a perfectly balanced tire and wheel combo can cause some definite vibrations at discrete speeds if the tires are not round. In this day and age, where tires cost less than they did 20 years ago, the roundness of a particular tire is certainly a concern. This roundness is never mentioned by the manufacturers or the dealers, yet it can be a significant issue.

See if you can mount a piece of chalk or a pencil point on the floor so that it contacts the tread. Rotate the wheel so that the point just contacts the tread at the highest point of the tread. Now rotate the wheel 180 degrees and look at the gap. A very good tire will be 1/16" or less. A poor tire will be 1/8" or more. You'll feel 1/8" on a W126.

I had the tires balanced and rotated, but the vibration persists. I think it is the idler arm. It still wiggle. I torqued down the bolt more, don't know the exact torque, I guestimated it to be 80-90 ft-lb(?). The steering rack seems to wiggle less it the 9-3 position on front passenger afterward. No wiggle in any other position, not on the driver side. I will take it out tonight to go to work and see how it feels. Everything else that I've done seem to be buttoned down. As for the steering shock, I bought a new one and took out the old. I compared the compression and the old one still feel good. I might as well replaced it.

The steering box would be the last to check. I did a search, but still confused on how to check this.

Thanks,

John

Well, I drove to work. Vibration is still there. I had the car aligned last week after the suspension work.

As far as play in the steering wheel, this was not a problem prior to the front end suspension repair. With the engine on, the steering wheel has about a one inch play on either side, which I read is acceptable.

The main problem prior to the front end work was the passenger side track rod and lower ball joint that had play causing the vibration. Now, everything is worse.

I check the drag link, it is tight, and no play in the tie rod. Something must be accounting for the play in the suspension!

I guess I will have to take off the front springs and yank the suspension around and see what happens.

Very frustrated.

John

Vibration is caused by some unbalance like bad tyres, worn engine mounts or things like that.

Play in the suspension or steering may make it worse but will not cause it. Excessive play lead to loose steering, wandering of the car, reaction to road conditions (more shaking than vibration). Bad steering shock leads to shaking of the car when crossing to transversal road disturbances, link repairs of the road and crossing railroad tracks, not vibration.

You can feel vibration of the wheels in the steering wheel, vibrations of the engine or transmission are more general and not more noticeable in the steering wheel.
What tyres do you have, some (all cheap) tyres are not suited for a Mercedes, these cars are very sensitive.

Before you start taking the suspension apart I would advise you to find the cause.

If you feel the vibration in the steering wheel start with testing (borrowing) a set of wheel that are tested with an other car.

If the vibration is not primarily in the steering wheel check engine/transmission mounts and drive shaft. Even if the vibration is only when driving it may still be bad mounts, under load the mounts are much more stressed than standing still.

Over the years I've had two friends that have battled front end vibration problems on their W126 cars - for some reason W126's seem to be very sensitive to wheel balancing issues.

In my case both problems were ultimately solved by finding a shop that could balance the tires with the wheels on the car. Not very many shops have the equipment to do this but if you look around you might be able to find one in your area.

If you can't find a place that does wheel balancing "on the car" go back to the garage that balanced your tires last time and ask them to do the following check. 1) balance one of your wheels on their machine 2) rotate the wheel on the balancer 90 degrees and re-check for balance. The wheel should stay in balance after it has been rotated, if it does not it indicates that the procedure for mounting the wheel to the balancer is not providing a consistent mount. The best balancers use a "pin-plate" mounting jig that secures the wheel to the balancer just as it is mounted to the car. These systems are the best way to mount a wheel on the balancer and in my experience they provide consistent and repeatable results.

I like Brian's idea about checking for tire roundness but I would also remove the tires from the rims and check for run-out. If have seen more than a few bent rims over the years, especially with aftermarket cast wheels.

I would go to www.gsp9700.com and use the find a dealer routine to locate a Road Force Balancer near you. It will find out of round tires, rims etc. and give you a paper print out.
IMHO, well worth the minor expense.

Steve

there are only two things that can CAUSE vibration[depending on how tight the steering is it can get amplified by other things]you have had the tires balanced properly so one down ,what about the brake rotors?a warped rotor will also cause vibration although usually at a specific speed as it tries to knock the pad back into the caliper[and vibration under brakes may not yet be apparent] i had the same issue with my own 420sel and that was the issue.

__________________
David S Poole
European Performance
Dallas, TX
4696880422

"Fortune favors the prepared mind"
1987 Mercedes Benz 420SEL
1988 Mercedes Benz 300TE (With new evaporator)
2000 Mercedes Benz C280
http://www.w108.org/gallery/albums/A...1159.thumb.jpg

For years my 126 drove me crazy with vibration. I could get new tires, get them perfectly balanced, and it would shake like crazy. I drove the tire guys mad, insisting they replace the tires and doing re-balance.
I replace every part under there, and adjusted the steering box and the wheel bearings numerous times.

Then, after a perfect balance job on new tires, using the vaunted Hunter force machine, I had the same old shake-shake-shake. But, I discovered I could just remove a wheel/tire, and put it back on again, and the vibration changed or totally went away.
The only thing I could deduce was that the wheels were not perfectly hub-centric, even though I could put a dial indicator on the two front ones when the car had the shakes, and get virtually zero (0.010") runout on the wheel rim.

Finally I gave up and ordered new wheels and Goodyear Assurance tires from the Rack. All was smooth! But then I found a cosmetic flaw in a wheel, and had to dismount the tire and replace the wheel. Sure enough, when the new wheel arrived, I had the tire put on it, force-balanced on the Hunter - and it shook. We tried a 2nd balance - it improved a bit but still not perrfect.
I put it on the rear, and all is now good, but I dread the time when rotation comes.

But the comment about tire roundness is probably valid. These new Goodyears are their finest tire, but I can see significant vertical runout on all of them, maybe not 1/8" but enough to easily see when spinning the tire.
I have similar runout on the tires on my other cars, and no shaking at all, ever.

So, I submit that the 126 is the most vibration-sensitive car in the known universe!!

good luck,
DG

Another confirmation of the quality of Goodyear tires...........all advertising..........no product.

The shaking that I am experiencing is not just a vibration at 50+ mph. It is a violent shaking, that the car almost seem to lose control. The whole front end of the car shake, not just in the steering. I have to drive it under 50 mph, then it seems fine.

The warped rotors may be a possibility. I may have to get a dial indicator and check the run out on them. When the car has the violent shaking and under braking, the vibration is enhanced, but not at speed below 50 mph.

I will replace the steering shock and check the center link again. I will bleed the front end caliper and see. I may have not put the pads back in correctly.

Will update as I find out what the problem is.

John

Vibration is very different from shaking. Vibration is annoying but does not feel that you are losing control.
Shaking is a suspension problem, not tyres (unless they are very bad).
If it is speed related you can look at the brake reaction bar and all rubber parts. If these are worn the toe-in may vary to much under load. Also check the stabilizer bar, the connection to the top control arm sometimes break.
Tyres are always important for a Mercedes. In my experience Michelin tyres are the best.