vibration at speed

[WGHungerford]

I'm about ready to give up! I have owned this '73 240 for 22 years, and it has always had a small vibration at speed, usually 70 mph....and in right hand corners at speed it really shakes. I just got it back from what is supposed to be the best suspension shop in town, and they can't figure it out. Everything has been checked out, bushings, u-joints, etc. Anybody got any bright ideas? Thanks.

[hmsports]

Has the shake gotten worse recently? Or has it always shaken the same since you got it?

Is the vibration felt in the steering wheel or where?

I'm not sure all the things the shop checked, but here's a list of items that could make a shake in the front end...

Ball joints

Tie rods - both inner and outer

Tension Control arm rubbers worn

Steering rack rubbers worn or lose

Strut tower topper may be worn or lose (not likely)

Control arm busings

Spindle nut lose

Wheel bearings worn

Incorrect toe

I'm sure you've rotated your tires but maybe it's a bent/out of round rim.

Was the car involved in an accident before you purchased it?

More details may help.

Rick

[2ManyZs]

Given that the vibration is worse in a right hand turn it pretty much rules out a driveline vibration. It is more than likely a suspension problem or possibly steering related. I'd have another shop take a look see. Never hurts to have a second opinion.

Is it possible you may have a wheel that is bent? Or possibly a tire out of round? Have you tried to rotate the tires to see if it makes any difference?

My first assumption would be a bad bushing somewhere in the suspension. Since it is worse on a right hand turn the first place to look is the left front , since you are loading that the most in a right hand turn. I'd check the wheel bearings, tie rod ends, T/C rod bushings, ball joints, wheel bearings, rotor and caliper (possibly warped rotor?)wheel and tire on that corner first. Also check the inner tie rod end and steering rack bushings. Then if the problem still persists, go to the left rear corner and check everything there. Work your way around the car one corner at a time and hopefully you will discover the problem.

[WGHungerford]

This vibration is not coming from the front end. I have had three sets of rims and three sets of tires on this car over the years and the vib has always been there. I do notice it more when there is some additional weight in the car, passenger, misc. cargo.....and the funny thing is, this vib at speed is increased on right hand turns only. I dunno. Thanks.

[hmsports]

Ok then, how about these items to check in the rear...

Mustache bar bushings

Half shafts for play

Differential carrier bearings worn

Rear wheel bearings

Brake drums out of balance - maybe some fins are missing or the counter-weight plug is missing

Toe is off

Check the screw-in cap on top of the right rear strut - maybe it has worked out and the strut insert shaft is wobbling

Check strut inserts to make sure they good

Control arm busings for wear

Half shaft u-joints

Maybe if the half shaft were out before the mounting plate where they mount to the pumpkin or wheel is cocked a bit

Check that all bolts holding the control arms are tight

If there is a rear sway bar, make sure it's mounts are good - and that it isn't binding

Check the strut-mount insulator

There's not much else that I can think of.

[WGHungerford]

Well, you've given me some good ideas. I negelected to mention that I have installed struts and had the differential rebuilt to no avail. Thanks for the info.

[2ManyZs]

Whew, every idea we come up with has already been taken care of it seems.

One other item, when they rebuilt the diff did they replace or have you since replaced and/or checked the front diff mount?

[59ghia]

How about a bent front or rear stub axle? I have no idea how to test this, maybe jack up one corner at a time, and spin the wheel? Put a dial indicator on outside of rim and spin? Or have a friend drive alongside of you and check the wheels at speed? Using cell phone in this situation helps communicate better.

Just some ideas

[WGHungerford]

Don't know if front diff mount has been replaced. I'll have it checked. I've thought about the half shaft deal too. I have been playing with this problem off and on for so long now. After awhile I just get tired of it, and drive it. Never seems to change. I think there is just some geometry out of whack. I'm going to take it to a shop with a dyno, run it up, see if ......... Thanks guys.

[halz]

Has the car ever been in a prang? (before you owned it?). The fact that a reputable suspension shop found nothing and that you've tried different sets of rims and tyres suggests maybe the problem is deeper than suspension/wheels. Not sure of the right place to go...perhaps a panel shop which has a chassis jig. They should be able to check that the chassis is true and square. I guess what I'm saying is that having new or reconditioned suspension components is no good if they are attached to a bent chassis. Just a thought... (and I hope its nothing that serious:disappoin )

[WGHungerford]

Man, I hope it's nothing like that! There is no evidence anywhere. You know, I'm finally at the point where I want to rebuild the engine and repaint. I surely love driving this rig. I don't mind if I have to pay, I want it fixed so I can move on. After this next trip to the suspension shop and dyno test, I will try the frame shop routine. Thanks.... I think.