[Gary00SLS]

I looked around the forum and hadn't found any posts yet on the existing issue of tire shake/bounce. Forgive me if I've missed it.

First let me ask this: What are OEM tires for the Seville SLS/STS?
(Mine is a 2000 model.)

At just around 65-68mph, a certain shake begins. Like a tire out of balance or bad belt type of shake. These tires are new (as of March) Goodyear Infinity's (OEM size). The dealer insists they can't find anything wrong, must be the road surface, and the car is very sensitive to the road. BULL!! Something is causing a shake.
I had the tires balanced both by the dealer and by Sears Auto Center where I happen to work and I did the work myself. Calibrated the balancer and balancer them from scratch. Still, same speeds, same shake. Tried increasing tire pressure to 40 psi, still the same.
On another forum, this issue was addressed and many others are experiencing the same frustrating situation and lack of resolve. Even GM can't find (or maybe wont admit) a problem.

Help! I want my classic Cadillac ride.

 

[elwesso]

It could possibly be bad rotors..... maybe.......

 

[Gary00SLS]

It could possibly be bad rotors..... maybe.......

Rotors turned. Tires balanced again, just today. Could the rotors be that far out of balance or do rotors go out of balance? Besides, it's more of a out of balance shake not a vibration. Rotors would be a hi frequency vibration, wouldn't it??

 

[Katshot]

Unfortunately, Your car is one that has "special" needs when it comes to wheel balancing. It's a fairly common issue with your type of car. Check out the link: http://www.broadwayautoclinic.com/Balancing.htm
and get your car to a shop that uses one of these machines. As I recall, the site offers a list of shops in your area that have this equipment. I've talked to other FWD Caddy owners and they all swear by this procedure.

 

[the Sandman]

The Hunter GSP9700 Road Force Wheel Balancer is great - I have mine done on it all the time. Click this link to find the location nearest you.

 

[Gary00SLS]

The Hunter GSP9700 Road Force Wheel Balancer is great - I have mine done on it all the time. Click this link to find the location nearest you.

I have one in town. I'll have to give them a call to price it's use. Then I'll have to approach the Cad dealer to pay for it. They had to do this to my Honda CRV. Still didn't take 100% of the shake out of it, but I didn't pay for it either. I'm really having mixed emotions about the service I am receiving at my local dealer. I only have one! I'm screwed.

 

[SoundAdvantage]

I have a "Bubble Balancer" you can use just kidding > but seriously i am experiencing the same Exact problem with my 87' Deville at different points between 65 and 75 mph. But at 0 to 60 mph and 80 to 85 the car has no vibration. I think the issue on my car is i have 2 new tires and 2 older Goodyears that still have good tread but need replacing. There are a number of things that will cause a vibration on a vehicle > A Tire or Wheel out of balance OR Out of round >Loose or Worn Wheel Bearings > Worn Tie-rod Ends > Worn Balljoints > Excessive Wheel runout > A Blister Or Bump on a Tire. Sounds like you need a Good Mechanic that Knows Cadillac cars inside and out. Screw the Dealers. :spin:

 

[elwesso]

Even a small bulge on tires can cause a felt vibration...... Centrifugal force........ A small bump may be noticed slow, but once the tire sort of "stands up" (ever seen how dragsters tires get really tall after they go, same principle), it balances itself out.......

 

[El Dobro]

There's a bulletin out on the shake problem. It starts out with balancing the tires, then try "screened" tires and as a last resort, change the lower control arms to the ones that were phased into production mid '03. They have different bushings to better isolate the shake.

My '98 SLS has the shake around the 65mph area, but it does not do it all the time. It does seem to change along with changes in the road surface.