Paul330

My new Z06 has a shake at highway speed. First thing I'm going to do is have the wheel balance checked. Is there a specification to which Z06 wheels should be balanced? I'd like to know what reading on the balance machine is acceptable vs. unacceptable. I figure for a car that can do 198 mph, the balance spec should be pretty tight. Thanks.

flycastinguy

Find a shop that uses a Hunter Road Force balancer. It's impossible to mfg a perfect wheel or tire. Wheels and tires are both a little out of round. The Hunter machine will position the tire on the wheel in an exact position to yield the best combination balance. Properly done, it's silky smooth.

gonzalezfj

This is the best way available today to balance wheel/tire assemblies.

allanlaw

It's balanced to spec when the display reads "0.00"

LGR

The rest of the story, and the most important part. Under 10 pounds of road force. (we see 0.00 balance and 50-70 pounds of road force quite a bit)

Paul330

Thanks. The dealer raod-force-balanced my wheels today. They said the as-left approximately 30 lbs of road force was acceptable. It is much better than before (55 lbs), but there's still some shake in the front end. I like your idea of 10 pounds or less; that's the kind of advice I was looking for.

My experience with road-force balancing is that the effect will not be perfect and it will also be short-lived; as the tire wears, the wheel will need to be road-force balanced again. I think the tire manufacturers should just make their tires round in the first place - especially for something they're calling "super car" tires. Installing a weight to counteract out-of-roundness is not a perfect solution, but instead a compromise to compensate for a defective tire.

LGR

The idea that you can properly balance an "out of round/high road force tire" is a game. Even if the tire is in perfect static and dynamic balance, the spindle of the car still goes up and down as the tire rotates leading to the shake felt in the car. The 10 pound spec, I don't think is written anywhere but comes from a LOT of testing. I don't know that GM has any spec on road force but 10 pounds is the number that seems to be the standard to fix about all cars.

LGR

From a friend at Cadillac:
"This may be the problem. The road force balancer will fix these in my experience if you are persistent. Most important is you have to drive the car 10 miles and then IMMEDIATELY get the car up in the air, get the tires off as soon as possible, check the road force, and get them BELOW 10 LBS OF ROAD FORCE. I don't care what specs are, once they have felt the vibration, they will not accept anything over 10. Even if you have to go through multiple sets of tires to get less than 10, do it, match and hub mount to get them as round as possible.

If you are taking it somewhere else, I bet they are not getting them warm and fresh off the highway. Another key to road force is to use the animal fat tire lubricant, not the ru-glide, or rubber lube so many tire shops use.

They can be fixed, I have done them for other dealers who gave up."

LGR

This is the machine I have used:
http://www.hunter.com/pub/product/ba...159T/index.htm
P.S. be sure to watch the video

lemobile

Are the wheels are factory ?
If tire out of round make sure it is mounted properly on the wheel, if Ok just replace it, its should be under warranty.
I will not try to balance a out of round tire.

mousecatcher

what about on-car balancing (like on-car rotor turning). i just found a shop in my area that does this. i'd never heard of it before. they charge $35/wheel (wow).

mousecatcher

wheels aren't perfectly balanced either, so you'd still have to balance the tire/wheel. also, like you say, as the tire wears things will change and you'll have to rebalance anyway.

it would be way too expensive to make tires that are balanced.

mousecatcher

new car -- wheel balance does sound likely. but if you have access to another z06 or even c6 tires, it might be helpful to try a swap.

Paul330

My wheels are stock.

I can see using the road-force balance technique for slight out-of-round situations. But there is a point that, if the tire is too far out of round, that road force balancing will not be an effective solution. My suggestion is to start by balancing the wheel/tire (not using a road-force balancer). Then put the wheel on the road force balancer, and see if there is any road force. If road force is above x, then the tire should be discarded because it's too far out of round. I'd like to know what a good guideline for x is. Previous post said 10 lbs as-left is ok. But from how far out can you expect to be able to bring it in from?

lemobile

Stock wheels, can you tell which one, it can be all of them.
This should be under warranty, if you have a friend with a ZO6 try to swap them.
I have HRE wheels on mine and no problem at all.

Paul330

They're the '09 silver painted spider style wheels. Thx.

RC45

Aren't all the new factory Corvette wheels made in China these days?

Just thinking out loud here.....

lemobile

I am curious, is the vibration on all the roads or you just happen to drive the same section of freeway or highway and feel the vibration ? On one section of a freeway by my home I will swear then all my tires are out of balance till I exit for the next freeway. (I can feel it as well with my Impala SS)

When I asked which one, I means left front, right rear ??? they can not be all out of round or balance. Can you feel which one ?

I will not spend any dollars to get it fixed, it should be done under warranty if a wheel or tire is defective. For sure it can not be the 4 of them unless GM have a serious problem with the new wheels type, if this is the case you will not be the only one.

Cape Cod Bob

Have an 08 Z06 that I bought new in October 2007. Been searching and trying to find someone/anyone in the MA area that knows, really knows, how to use the Hunter and balance my wheels. Been to the dealer, another dealer, and a Goodyear store.
My gut feeling is that GM chrome wheels are crap. But, I could be wrong.
The dealer has replaced the RF tire that was out of round from the factory.
Now, at 9K miles, the issue continues. Doesn't really show up till about 70mph and up.
So, any suggestions as to anyone with a late model Hunter balancing maching that CAN balance the tires, or detect the problem...in the MA/RI area?
Also notice the steering seems vague as the speed goes up. All 4 tires at 30lbs cold. Have had 2 alignments to "stock" specs too!
Had an 06' ZO6 and never had these problems.
Bob

LGR

"I can see using the road-force balance technique for slight out-of-round situations" That is NOT what they are for. You can have tires that rotate perfectly straight (side to side and up and down) and road force be sky high.