To those who have wrecked their suspension and fixed them... Help!

So some of you might recall my story of the pothole on I40 last month; I bent the front wheel on my 08 coupe pretty bad, and took a hit to one of the rears, as well. Anyway, there appears to be no real damage other than the two wheels (LF, LR), and those have been replaced with a nice set of chrome 08/09 split spoke replicas. The brilliant "technicians" at the local tire place (authorized Goodyear EMT dealer) have given all 4 tires a clean bill of health, and the rims and tires are on the car and looking good. The mount and balance presented no problems, and in fact the guys said they "didn't need a lot of weight" to put them perfect.

Problem is, they shake pretty bad at freeway speed. The steering wheel just shakes back and forth and makes this formerly perfect car an instant POS. The wheels were balanced 3 times and still, it shakes. The confusing thing is that every time, the wheels are "perfect" according to the balance machine; even after a "calibration". Also confusing is the fact that the shakes come and go, even at the same speed. One minute it's almost perfect, the next, it feels like the lugs are loose.

I still need to do an alignment only because it's the right thing to do after a hit like that, but it's obvious that nobody gives a damn about your car when you bring it to a shop, so I'm looking for any expert advice from the board before I turn it over to ANOTHER shop.

I know my way around cars, but this is my first Vette.

So some facts:
The rims are true.
One tire shop says the balance is "perfect" on all four wheels.
The tire "experts" indicate the tires are still good (no obvious defects).
Alignment is not "obviously" off.
No noticable damage to steering or any other suspension component by feel or inspection.
Steering wheel shake comes and goes.

So WTF? Anybody have any good ideas about the Corvette suspension and its "weak points"? Anybody wrecked one on the street or track day and gotten it fixed to your satisfaction? What was replaced?

Thanks very much.

 

Do you have a friend who can swap out wheels for a test? It sounds as though you have a busted belt in one of your tires. Even though they look perfect and balance on a machine they are not being subjected to the weight of the car at speed. Swap the wheels and drive the exact same road at the same speeds and see if the problem surfaces. If it does its suspension related, if not new tires.

 

After an impact severe enough to wreck the wheels, I'd get an alignment ASAP and see what happens.

 

Take a look at this thread and scroll down to the picture in post# 6 to see a picture:

http://forums.corvetteforum.com/c6-t...ation-wtf.html

As explained in the thread, what you see in the picture is a rotor that still has those Tinnerman nuts on the lugs.

You say you have "replica" wheels, so there's a good possibility that they may not have the countersunk area inside around the lug holes that the OE wheels have.

If your wheels don't have the countersunk area, and if your rotors still have those Tinnerman nuts on there, then the wheel won't mount up flat and square to the hub and you'll get that vibration you're experiencing even though the tires/wheels are perfectly balanced.

Anyway....worth taking a look, and if you still have those nuts on there, remove them.

As has been mentioned, check the alignment.

Bob

 

The rotor clips are still there, and I admit I don't know if the bolt holes are countersunk... I will remove the offending clips today as soon as I get home and report back. After reading the thread provided, I'm sure this is it. Thanks much!

 

NOPE!... The "clip removal" mod didn't help. Besides, these wheels have the countersunk area to clear them.

Looks like the next step is to get the alignment done, then see if I can get the tire shop to take another look at the rubber; perhaps it is damaged internally. I wish I had another buddy with a C6 to swap wheels with, but no such luck.

If any other ideas, I'm all

Thanks much! Will keep you posted.

 

have your wheels balanced by a shop with a hunter road force balancer. go to the hunter website to find a shop near you. this balancer has a load wheel that loads the tire to the same weight as your car has on each wheel. also check run out on each tire. if the impact bent your wheels, the tires may also be damaged. replace as neccessary. my c6 went through the same thing. i replaced the rims and tires that were damaged. no problems. hope this helps,

 

Dayum!! Sometimes the simple and easy fix works, but in this case I guess it's gonna take some more messin' with things.

Good luck,

Bob

 

Tire.

 

IMHO it seems that a hit hard enough to bend 2 wheels is surely enough to play havoc on the alignment! That would have been the next item that I WOULD do after replacing the bent bits. I think you will find there are issues with the alignment.

 

Alignment will not likely cause a shake in the steering wheel but rather poor handling or problematic tire wear. If your still using the tires you had when you bent your wheels there is likley tire damage even if you can't see anything.

 

Have you thought about the front shock. I'd bet there may be internal damage that would cause a tire hop. you can always have someone drive along side of you to watch what the tire is doing.

 

Should this say alignment, suspension damage? Some loose/bent fittings could most definitely cause some shimmy/shake.

 

The dealer has a road force balancing machine, so I think that will be one of the stops. I'm thinking that there may be some hidden damage there and the road force balancer will show that. I'll have the alignment done with them as well.

Front shocks aren't leaking or loose, but the problem is a side to side action felt in the steering wheel, not a bounce. It's certainly worth a closer look though.

 

I have to agree strongly with the alignment. If the hit was strong enough to trash two wheels, your alignment got trashed badly. Stand back from the front of the car enough that you can "see" both front tires in relation to the rears. Look down the sides for your toe on the wheels and camber. Willing to bet you will see a huge difference. If anything is way out of tolerance, the tires could be jumping on the pavement while you are rolling which is quickly trashing the tires as well as the suspension. Some simple things you can do yourself also would be to jack one side of the front end and see if you can move the one tire off the ground in relation to the steering system...looking for whatever could be loose. For the rear, block the front wheels, jack the rear up totally. Start it up, turn off the traction control system, put it in gear. Feel for shaking. Remember that the rear half-shafts basically have CV joints in them and you may have damaged the one.

 

I'm putting my money on the tire(s). I think you have a broken steal belt in it causing it to vibrate...

 

My only thought on that is if he was able to get them to balance, then the belt wouldn't be out of place. I agree whole heartedly with you though that this would have been the first suspect item.

 

The plot thickens!

Couldn't get the the alignment shop today, but it is very high on the "Things To Do" list... I did stop at the tire shop to tell them their balance didn't work , and I would be going somewhere else for a new balance (with the road force machine). I was looking for credit, money back... something. Anyway, he wants to put it on the machine again and check for tire problems. So we spin it up, and the freakin' rim is out of round by about an 1/8 inch! ...I saw it with my own two eyes. Other front rim is the same way. But it DOES balance. So I vibrate my butt back home and decide to do a runout check with the rim bolted to the car. Results: Both rims are nearly dead true! Only one had a slight out of round condition, and it was only about .030 inch. So it appears that the rims are true to the bolt circle (lug centric), but not true to the hub (hub centric). Of course if it is balanced to hub centric on the machine, it will be out of balance on the car.

So now I've got a problem identified, but no solution. I think my options are:
1. Go to another shop and try another machine;
2. Figure out how to balance the tire using the bolt circle as reference;
3. Machine the wheels to true up the hub center;
4. Get a new Corvette.

You've all been a big help so far... Don't quit on me now! Anybody got any other ideas?

 

Hmmm ... aren't our wheels SUPPOSED to be hubcentric?

 

OEM yes, Clones often arent....I'd send those wheels back..