Hi all,

I've got an '87 300D w/ 256Kmi. Driving to Montana and back and the winds across South Dakota, Nebraska, and parts of Montana REALLY blew the car around. In Nebraska, steering was "approximate" holding the wheel hard.

The front control arm bushings, ball joints are <10,000 miles old, rear links are <1 yr old (except subframe bushings and inner contorl arm bushings). Shocks are Bilstein, about 75Kmi on them, one rear shock leaks a bit. Steering linkage replaced about 65Kmi ago, steering damper about 30-40Kmi.

Even back home in TN the car does not seem to handle precisely. Sometimes its better than others. Really flat smooth roads are best.

When on the lift, the subframe mounts are cracked but they do not appear completely collapsed. They are probably original. The rear tires are wearing perfect. Front tires wear well too.

What is the likely culprit?

Thanks,
Brian

(I accidentially posted this in Diesel discussion as well, sorry).

What are the tires and tire pressures that you are running on this car?

Have a great day,

idler arm(s)

__________________
1985 190D 2.2l Sold-to Brother-in-law
1996 Mustang 3.8l -"thinks it's a sports car"
1988 Grand Wagoneer - Sold (good home)
1995 Grand Cherokee Ltd -"What was I thinking??!!"

How about the idler arm bushings? Very common problem. That would do it.
Any of the many balljoints in the steering linkage that were not replaced would also be suspect.

Also, how much play is in the steering before the steering arm starts to move?
Sometimes play in steering box or the steering wheel shaft linkage can cause for rough going on windy days.
This is also very common.

__________________
1986 300E 5-Speed 240k mi.

The idler arm is a few weeks ago, the steering linkage is tight. As for play, I don't think there's much. Tires are Michelin MXV4 29/31 psi with 6300 miles on them. I found that increasing from 29/29 to 29/31 made the ride a bit better - made the change while on the road in Montana.

Brian

How about the steering dampner?

You might have bad rubber bushings on the rear suspension arms.

Increasing downforce on a w124...

__________________
John

2003 Firemist Red/grey leather SL 500
2015 Palladium Silver/black mbtex GLK 350
1987 Smoke Silver/burgundy mbtex 300E Sportline (SOLD)

Click to see 87 300E

I have never had the problem with the rear suspension arms, but I've read/heard descriptions. It would certainly be worth raising the rear and shake around on all those joints and there are several to shake.

I really believe you need a little more tire pressure. The pressures listed in the fuel tank door are minimums. I don't, however believe that this is the source of your problem though. With that little pressure you may very well see premature tire wear down the center of the tires, especially the right rear.

Best of luck,

Larry,

Why the right rear?

Brian

I took the car to an independent different than I normally use. He found that the car handled pretty well for having 256Kmi. All suspension components are tight . Shocks pass the bounce test, but when moving steering wheel back and forth on freeway he said it didn't feel right, like rear of car was on its own.

Their conclusion was that shocks are probably weak. The rear right one has a slight leak, and the dust covers on the fronts are not really correctly installed allowing for dust.

I'm going to get them replaced with either dealer, Bilstein, or HD Bilstein shocks. Any recommendations on which are preferred? I currently have Bilstein (comforts) and they nearly seem like HD's to me...

Brian

The diagnosis seems a bit odd, but I strongly endorse the HDs.
I would question the need for replacing the front struts.
How old are they?
Perhaps try the rear first, and see how it feels?

__________________
1986 300E 5-Speed 240k mi.

Shocks are easy for shops to replace and to make money on. They can replace them with no knowledge about your car and make money. Did they shake on the rear links looking for bad bushings. If they did not, find another shop.

I don't know why the right rear wears worse than the left rear, but I just know that it happens. I've maintained over a million miles worth of these cars, mostly 123's and 124's and I've seen it happen too many times. Keep plenty of air in the rear tires particularly.

Good luck,

Larry,

Interesting comment about the right rear. The shop is well regarded, at least within MBCA. I believe they checked all bushings and links (all of which had been replaced, anyway), they checked to see if steering was too tight, tire pressure, and noticed a small amount of feathering particularly on my front left tire.

My front left tire typically shows a bit more feathering than any other tire, and the rears look like they're wearing perfect.

It may just be mind over matter, but it seemed that on my trip to Montana and back (6300 miles) that the front left OR right tire would show a bit more wear from time to time, possibly because of the very strong winds and I was really holding the steering wheel to keep the car from blowing into other lanes.

Either way, I'm going to replace the rears (because one is leaking) and probably the fronts as well. In part because I'm just tired of them and possbily because they'll solve the problem. I expect to do the work in October.

Thanks for the suggestions,
Brian

'I believe they checked all bushings and links (all of which had been replaced, anyway), they checked to see if steering was too tight, tire pressure, and noticed a small amount of feathering particularly on my front left tire.'

'My front left tire typically shows a bit more feathering than any other tire, and the rears look like they're wearing perfect.'

Quick diagnostic: swap wheels front and rear and see if things improve. If so, the alignment is NOT right, and/or parts are worn you haven't located. When I did this, dramatic change in handling, even though all tires looked pretty good. I left the tires this way when getting the alignment.

Note too if you are just visually checking the rear suspension, you won't see loose mounting bolts. Everything looked fine on our 190E, but vigorously shaking the rear wheels while on the ground showed SOMETHING loose on one side. Turned out to be a track strut bolt.

Test the steering with wheels on the ground. Watch for what moves while someone turns the steering wheel just until resistance is felt (engine off). You'll see what moves the wrong way at the pivots. I found too much play in the idler bushings - easy replacement.

Steve

I've read on the Easley/Ritter list that worn rear subframe bushings can cause the symptoms you describe, where "the rear of the car feels like it's on it's own." Several folks on that list have reported that replacing those bushings can really tighten up the way a car feels.

__________________
Steve
'93 400E