Suspension component testing ck list needed.....

[C@lvin]

I need to replace the left upper spring seat on my 98 S70 (191K) and want to replace any other failed or near failing suspension components at the same time so that I only have to pay for an alignment once. My front tires are wearing on the outside edges and I have also been having an occasional clunk on the right side but have not been able to determine the cause.

It would be extremely helpful if there were a list of each component along with both a way to test or check it as well as the most common symptoms of its failure. I've been able to find some of this information but it requires a lot of seaching so I thought it would be great to try to consolodate the related information into one place.

Here is a suggested starter list and I'd be grateful for any additions to it or explanations for testing and common symptoms. Also, I am interested in the front suspension, but feel free to add information pertaining to the rear.

Front:
Control Arm Bushings
Ball Joint/Control Arm
Sway Bar End Link
Outer Tie Rod
Inner Tie Rod
Strut

Rear:


Thanks in advance!

[larryh]

You can feel them and look at them when you take the front end apart. But If the parts have 80K+ Just do it all at once and don't look back.

[jblackburn]

Phew, ok. I'll chime in what I know from what I've dealt with on my cars.

Control Arm Bushings

Ball Joint/Control Arm
Look for cracked ball joint boots and leaking fluid. Also, if the car pulls significantly in either direction with no hands on the wheel, you may have a busted or bent control arm.

Sway Bar End Link
Usually results in clunking and looseness in corners. Take the tires off and give the bar a good shake.

Outer Tie Rod
The outer rod can twist but it should be fairly difficult to do that. And there should be no "looseness" detected in the joint itself.

Inner Tie Rod
Shouldn't move AT ALL.

Strut
Spring mounts will cause a clunking and will be loose/spin under the hood. Bad struts will result in more than one bounce if the fender of the car is pushed down on or the car is braked to a hard stop.

I was going down I-295 around Richmond once, where there are bumps and potholes everywhere in the road, behind a car with bad shocks. That thing was bouncing all over the place

Rear suspension:

Most common problems are bad strut mounts and delta link bushings (usually result in a clunking or excessive play in the rear suspension).

[C@lvin]

Larry brings up a good point. Is there a commonly accepted life expectancy for each of these components? I guess Larry would suggest 80K.....

Also, what about the control arm bushings? Can anyone suggest how to check them or what symptoms of failure are for them?

Pictures might help a lot too. Anyone have pictures of failed suspension components?

Jablackburn, you mention "clunking" as symptoms for both spring seats and sway bar end links. I get an occasional, single clunk while doing low speed turns (like pulling into a parking place). I don't get the clunk at speed and it's not associated with going over bumps. Would you say that's most likely the sway bar end link?

Finally, is there anything among these components, beyond simply being out of alignment or chronic tire underinflation, that would lead to the extra wear on the ouside edges of the front tires?

Thanks again.......

[jblackburn]

Everything on my car to my knowledge is original at 166K, with the exception of the left spring seat and control arm, which I screwed up jumping a curb trying to avoid an accident, and the sway bar links. About 45,000 of those miles are mine. I'd say the typical lifespan for most things are about 100K miles, struts maybe 150. It really depends where you drive though.

Sway bar endlinks will usually clunk over bumps, and going around corners when the weight of the car is shifted around...not so much at low speeds like parking.

Spring seats tend to be more of a rattle. I've got my bad one in a box in my trunk - I'll take a picture of it later, but I'm sure there are already several around.



The control arm bushings will simply LOOK gone. Rubber deteriorates over time, these usually go sooner than most other suspension components I believe.

CV joints are another thing to add to that...I replaced both of my axles because they were clacking (usually a couple clunks) on tight turns and the boots were torn.

Yours might just need to have the steering stops greased if all you're getting is 1 clunk on tight turns. It's worth a shot anyway...it takes all of 5 minutes and a can of grease.

Control arms (or bushings), collapsed spring seats or strut mounts (rare, but still possible), or simply a bad alignment can cause the tire edges to wear quickly. These cars are knocked out of alignment VERY easily compared to anything else I've ever had (stupid potholes!)

[C@lvin]

Thanks for the reply. No need to post the failed spring seat picture for my benefit since I've been there and done that (though it may help others - like you said there are other pics of that posted various places) and i already know I need to do the other side. To me, the failed spring seat makes more of a creaking noise going over bumps but I've heard other people say their's clunked.

I'm actually getting the tire wear on both sides. I replaced the right spring seat and got an alignment about two years (30K) ago.

My CV boots are good. I always thought that the CV joint clunking would be pretty repetative while turning versus one or two clunks?

I never knew bad spring seats would cause the outer tire edges to feather but I ain't no mechanical engineer either. I let it go on the right for a few months before replacing it and now the left seat has been shot for several months.

If I can't identify any other problems I will do the left spring seat, get an alignment and hope for the best. I just have a sense of urgency about it now becuase I put new tires on all four corners this morning.