This has been ongoing for a couple months now, I don't routinely go on freeways so it isn't a big deal but in the meantime I've been throwing parts at it to no avail. I've got 360,000 miles so I don't mind throwing parts at it as I plan to keep this car for awhile, engine and tranny are perfect.

The shaking usually starts mildly around 55mph and gets pretty bad around 65-70. What is odd is that every now and then it will feel fine, then the vibrations slowly start happening again. The rest of the car doesn't seem to be vibrating much, just the steering wheel.



Anyway, here are the parts I've replaced recently trying to figure this out:

Wheels
tires
inner tie rods
outer tie rods
struts
strut mounts
control arm bushings
brake rotors
alignment

ball joints were replaced a year ago

It's gotten a tiny bit better but nothing dramatic. The rack is not the original, previous owner replaced it around 3-4 years ago. It's got a ZF stamp. I've had a lot of 80's MBs before which all had steering gearboxes so I'm not super familiar with troubleshooting racks. It feels pretty tight, little to no slop.

I am also an amateur astronomer and this hobby takes me down some washboard dirt roads that can get pretty hairy but I'm pretty careful to keep the car from ever bottoming out. That being said I do routinely carry a large amount of gear (300lbs+) down these washboard roads for miles and miles which can't be too good.

I have a replacement pump I'm going to put it... not sure if it will make a difference but the current pump bearings don't sound too great.

There is a little bit of steering resistance on cold mornings (30-40f) for around 10 seconds but aside from that the steering feels great.

Any ideas? As I mentioned before, the car has plenty of miles and gets pretty abused, if I have to just keep throwing parts at it that is fine by me.

And make sure your wheels are free of mud, ice, dirt... whatever could be throwing the balance off.

Did a road trip a few years ago... bad shimmy. First gas stop in Wyoming, scraped off probably 5 pounds of mud from the wheel insides.

1000 miles and 3 car washes later, finally got it all out and smooth sailing....



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-Matt I ♥ my ♂

It's because that is usually the cause of speed specific vibration. 20+ year old wheels often have problems, and even new tires can have defects.

I have chased vibration problems more than once only to find that new, recently balanced tires were the cause. I like to buy my tires now at a place which offers free lifetime balancing, because you never know when you'll need it.

Just be sure your wheels and tires are well balanced and not damaged or bent before looking for other causes. The advice to rotate your tires and observe the change, if any, is a good (and free) way to check.

Have your wheels been checked for trueness? You could have them checked by a good shop.I have been going to an independent tire shop that is a family business since 1963!

The last time I got some summer tires, I had to bring in 9 alloy wheels in order to get 4 true ones! None of the bad ones looked bad. They did not charge to spin the wheels and check them.

You can do a rough test with a block of wood and about a foot of coat hanger. Put one end of the hangar firmly into the block of wood.

Jack up the car and put the block near a wheel. Bend the hangar so that its end is about 1/16" away from the outer lip of the wheel.

Spin the wheel slowly and watch for any in and out play, or up and down play.

I have also met a Brick owner that had a bent rear axle.

BTW - anyone out there need 5 slightly bent Argo wheels in good shape?
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'96 855R,'64 PV544 driver, '67 P1800 basket case, '72 Yamaha Rd400, '68 Honda 350-4, '12 XC70, the first 5 are mine, heh, heh, 525,000 miles put on 10 bricks James A Sousa

At one time, I had the same issue. At 52mph there was steering wheel vibration up to 56mph it smoothed out. Turned out to be the drive shaft was out of balance. Take it to a shop that can check and balance. Hope this helps.

I am assuming you have had the wheels balanced? How is the play at the wheel bearings? Check your wheels and hubs for abnormalities such as rust or corrosion build up. This can cause the assemblies to be cocked, thus inducing a vibration.
I would also go ahead and check the steering shaft along with the u-joints on the shaft. If I remember correctly there are two. Check the mounting of the steering rack. if all is good I would recommend removal of the power steering belt, that way you can rule out hydarulic issues. i cant think of much else but if I do I will keep you posted.
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Teach a man to fish and he will never go hungry. Teach a man to rob a bank, he will never go fishing again.

Hmm, can't remember if I have checked play in the wheel bearings! I replaced them over a year ago but I will certainly check this weekend. Don't have any rust, this car has been in socal all its life and is pretty rust free.

U-joints are a good suggestion, I'll probably replace those anyway. I will also be replacing the power steering belt when I do the pump this weekend.

When you say remove the PS belt, do you mean remove it and drive without power steering to see if anything changes?

Oh yeah and the wheels have been balanced properly. I had the vibration issue with the old Corona wheels and cheapo tires, I replaced them with Draco wheels + some decent BFGoodrich tires but it hasn't affected the vibration at all.

Yes remove the belt and drive without it. Be careful though because you wont have power steering. It wont be an issue trust me, Ive been driving mine like that for 3 months now, its not that bad. Anyways you said u replaced the tires with ''decent'' ones. Does that mean they are new decent tires or used decent tires? Used tires can have a thrown belt which would definetely cause vibration. I have even seen new cheapo tires ride like crap. Mind you I have mounted and balanced quite a few tires.
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Teach a man to fish and he will never go hungry. Teach a man to rob a bank, he will never go fishing again.

Replaced the pump and flush new fluid... problem has diminished slightly but it might be in my head. I'm going to have the wheels/tires carefully balanced again tomorrow and see whats what. I think I'll also replace the wheel bearings, now that I think about it I don't believe I ever touched them on this car. Doubt that will change a thing but it still needs to be done sooner or later!

My "new" 1990 240 sedan had beautiful Bridgestones on it which was part of my reason for buying that car (this being an experiment in cheap living). I forced myself to Live with them while fixed other items on the car. This lasted until the first snowfall when it go sideways with the mere touch of the brakes...date code indicated they were over

Long story short, my cheapo new Coopers on there now got rid of the exact same vibration. I knew I had a flat-spotted tire (from sitting) because when I rotatef them LR to RF and LF to RR the vibration changed from the steering wheel to the whole car!