rhunter

06 SC430: Recently bought new tires and rims - 18", 1/2" wider. Looks fantastic, runs good MOSTLY but get slight shimmy at 60 - 62 mph. Smooth as silk any other speed. Have less than 1000 mi on tires. Have had them balanced 3 times and switched fronts with rears. Still get shimmy at 60. Seemed to get shimmy more when applying gas slowly. Notice it less if let off and coasting. Any suggestions?

iolmaster

iTrader: (1)

Certainly can't say for sure but the 60 MPH shake is almost always balance.

Harold57

What tires do you have on your car? Does the shimmy go away after driving for 10 minutes or so? If so, they are flat spotting.

So when you say that it is shimmying, do you mean that you can feel the front end of the car shaking or that the steering wheel wiggles?

Coleroad

iolmaster is absolutely correct. When it's in a speed range like that, it's a balancing issue.

VVTiBob

No problems BEFORE new wheels & tires? How many miles on the car? Any pulsing in the brake pedal when applying the brakes? Yes, could be warped rotors. No, as others have already said tire/wheel balance. Probably the latter, were they road force balanced?

BUT.... you should read this thread VIBRATIONS starting at post #11

rhunter

Tires are Nittos and its not a cold tire flat spot issue. Can feel shimmy and see/feel in steering wheel.

Lawler999

have you used the correct wheel nuts ?

rhunter

No brake pedal pulsing. Don't know what 'road force' balancing means. Discount did regular machine balancing.

Thanx for the response. Just don't know what to do next.

rhunter

Paid lotsa money for new lugs to go with wheels.

rhunter

Thanx for the VIBRATIONS link. I read it but not being a mechanic I probably couldn't do a respectable "pre-load adjustment" on the steering rack. But I'm going to check around the Tucson/Phoenix area for a good front end shop and ask them about it. I was surprised to read that the SC has a built in tendency to 'shimmy' to various degree and speeds. I did not have a noticeable shimmy with the OEM rims and runflats but the ride was terrible. I'm super pleased with new tires and the better ride. I just think that for the price and the high end quality of the SC it ought to be flawless in all areas.

leexed

I would suggest to find a shop somewhere that can high speed spin the tires/wheels on the car. I have experience finding wheel imperfections that could only be found by simulating the car/wheel match. One possibility could be the lug stud holes off center. Found this on a new vehicle wheel. Only picked up when spun wheel on car.

OBP

I lived with a 60-65 mph shimmy when I had my Conti DWS on OEM rims. They were purchased at and installed by a Lexus dealer. Then, when I switched to after market TSW wheels and BFG tires, the problem went away. It just wasn't bad enough of a shimmy that I wanted to track down and address it. I either drove at 55 mph or 69+ mph and that was it. Now, when I get the shakes, I believe it is flat spotting because the problems go away after about 5-10 minutes of highway driving. And then only with two specific tires on the front. When I move these two tires to the rear, I get no problems at all. Not worth addressing in my view.

rhunter

** Discount tire was extremely helpful. Three or four balancing's but final fix might have been installation of what they called "hub-centrix" rings on all 4 wheels. They also replaced one wheel. Car runs smooth as a kitten now. Didn't know that when a wheel is 'universal', in terms of lug spacing, that the center hole diameter may not fit exactly. That allows for ever so slight misalignment of the wheel when mounted. Supposedly these hub-centrix rings help centering the wheel. Hope this helps somebody else.

Oldsig

That's great that your car is "smooth as a kitten now"!

Normally aftermarket wheels/rims come with the specific hub centric rings to mate the wheels to your vehicle...Well, I should say if you buy your wheels at a place like TireRack and specify identify the vehicle, they will include the rings. They are also available online if you know the wheel's hub size.

Bob

OBP

Wow, OP, how many miles did you drive without the hub centric rings ? Installer should have told you it was needed when they did the first install. Driving on wheels that do not mate to the hub and have no rings is definitely not recommended.