tennistodd

Greetings everyone! This is my first post in the SC forum. I recently traded my 06 IS250 in for a 03 Sc430. 1 owner, decent miles,LEXUS Cert. and very clean. My trouble is at 55 mph I get a shimmy in the stearing wheel and the wheels are balanced to perfection. I do have after market wheels (19") and the same problem existed with the stock wheels and runflats. Could the alignment be out even if there is no pulling? What should I look for? Please help if anyone might know. Other than this incident I am MORE than satisfied with my trade!
Thanks again
-todd

Lexiss_sc430

iTrader: (2)

Does it occur at any other speed? What are you doing to cause the shimmy, are u coasting, breaking, accelerating?

-Tommy

Edit: OH yea Congrats on the purchase, I remember reading your thread about wanting to take the leap over to the SC. Hope you enjoy your car!!

tennistodd

ONLY between 55 and goes away around 60. It happens through acceleration and coasting. The weird thing is it happens more times than not but I have noticed a few times it not happening? I am taking it to my tire people again tomorrow to see if they can find the problem again. I think I might get it aligned just to see?

jasonj

First time hearing this problem with SC430. I had a shimmy problem on my BMW E39 which is a very common problem for that model. It will only come between 55 and 60.

What helped me was applying higher tire pressure to all tires (40psi, when cold) and applying a same torque to all lugnuts by using the torque wrench. Not sure if it will help for your car, but give it a try anyways. Afterall, it costs next to nothing =)

Cheers,
Jason

Pearlpower

iTrader: (2)

Not an issue with SC430s like it is with GS400s which were tough unless updates were installed. I would rebalance those wheels again-try someone new.
55-60 is the sweet spot for unbalanced wheels to rear itself.
It is conceivable that your front rotors are warped but you can easily tell by the more dramatic steering wheel shake during braking.

Oh and welcome aboard the SC430 forum, time to change that sig of yours.

LexHou

I also just recently got an 03 SC430. I have the exact same shimmy that you have. I took it back to the dealer and they pretended to reapply a wheel balance that they claimed had fallen off.
I still have the shimmy. It comes and goes like yours, but it is still slightly annoying.

talwang

iTrader: (4)

hmm..I had the same issue when I put on my aftermarket rims.

I had them road force balanced 7 times , 4 wheel alignment twice and a set of 4 new tires plus I took my rims to a wheel repair shop for inspection, but the vibratin was still there after all that.

Finally, I went to a different shop and had a Japanese guy to road force balance these rims one more time and that vibration was totally gone since.

Anyway, make sure your rims are not bent and tires are not out of round.
If you have aftermarket rims, then you also need to make sure you have the correct hubcentric rings installed.
And find someone who knows how to balance your wheels correctly with a machine that is 100% properly calibrated.

dseag2

I don't think it's a problem common to '03 SC430s. My first SC was an '03 model. I had no shimmy with the OEM wheels and runflats or with the OZ Operas and Michelin Pilot Sports added later.

I agree with Pearlpower. You may need to have someone else look at the balancing.

tennistodd

Hey guys...Thanks for all of the comments. I had the alignment checked yesterday and it was out just a bit. I also had the wheels road force balanced again. (3rd time) Some of the vibrations in the rear is gone but the shimmy is still there. Last night it was BAD and this morning it is less? I JUST DON'T UNDERSTAND! It is making me sick. I am going to take it to LEXUS hopefully this week and have my mechanic there check it. I live about 2 hours from the dealer that is why I have let the local Goodyear store do the wheel change over from my IS. I don't think that it is in the rotors as it DOES NOT happen when I apply the brakes. Only at acceleration and deceleration. Thanks again for the replies and I will post when they get it fixed if it is possible?
THANKS
-todd
I will post pix and update sig this weekend when I get time.

Pearlpower

iTrader: (2)

Another issue could be a flat spot or out of round tire. Try rotating rear/front wheels/tires.

tennistodd

I would try that but I have 2 diff. sizes. 19x9.5 rear and 19x8 front. Tires are fairly new and I did not have this problem when the wheels and tires were on my IS one week ago?

martini3

I don't want to start a new thread since this one has the same symptoms that I've been getting for a few weeks now.

35-50mph = no shake, rattle or shimy.
55-60mph = a minor shimmy of the steering wheel on the freeway.
60+mph = it goes away.

When I brake hard enough, the vibration of the steering wheel shakes a little.
The braking is still very good but not good like it used to be. I tend to brake hard and sometimes w/ my windows rolled down, I can smell the burnt odor coming from my wheels. I park and they cool down.

I got 49K on my '03 and the last major tune-up maintenance was 33K which included tire balance and rotation.

I'm running 18's all around w/ Michelin Pilot A/S non-runflat w/ about 10-15K miles on them. PSI is 42 all around.

Never had an alignment. I will be getting one soon.

I'm taking her over to EM for a quick look and possibly tire rotation and check the brake pads.

I'll let you know what they find out. thanks...teeman3

Pearlpower

iTrader: (2)

Tee
Sounds like warped rotors and/or out of balance. For sure warped rotors.
let us know

tonydt1g3r

LOL Dude I've had the same exact problems also. Its that damn 55-60. I really think its a tire/balancing issue. Since I got new rotors

tennistodd

Well I guess I am going to buy new tires even though the ones I have are not too old. I have 235-35R19 on the front and I probably need 245's instead. Maybe that will fix the issue. STRANGE?