vibration

I have a 2000 Pontiac Bonneville, I recently had new tires put on and balanced, (same rating as before), I also had the alignment done, I was experiencing vibrations at high speeds (65 to 75+ mph), well after all the balancing, alignments and new tires all the way around, I am still experiencing vibrations, what can it be?:rolleyes: The problem was first noticed last year when I had to have brake service and the tires were rotated, since then it has been vibrating. I thought all the new tires and alignment would fix it, but it didn't.

I need some help!

Thank you

It'sa gotta be the tires! re-rotate yer rubber!

Where do you feel it vibrating? Is it in the steering wheel, in the seat or all over. As a general rule if it's in the steering wheel your problem is in the front half of the car, if it's in the seat then it's the rear of the car.
You may want to consider having the tires road forced balanced, it's a little pricy but can solve all kinds of vibrations.
Check this site out to find a location near you..

http://128.242.141.111/


Then there is also this..

On Aurora, Bonneville, DeVille, Park Avenue, Park Avenue Ultra and Seville models, a newly developed hydro-bushing lower control arm with improved damping characteristics has been released to offer an incremental improvement to the vehicle ride. The new lower control arms are designed to reduce but not totally eliminate the shake in the vehicle. Customers who have become "tuned in" to the shake condition may still feel some shake in the vehicle after the new lower control arms are installed.

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Lower Control Arm, Left (Aurora, Bonneville, DeVille, Park Avenue, Park Avenue Ultra, Seville)

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Lower Control Arm, Right (Aurora, Bonneville, DeVille, Park Avenue, Park Avenue Ultra, Seville)

Of course with the trans complaints you also have the trans may be the culprit in the vibration. Especially if the bulletin John posted is the problem.

I have a 2000 Pontiac Bonneville, I recently had new tires put on and balanced, (same rating as before), I also had the alignment done, I was experiencing vibrations at high speeds (65 to 75+ mph), well after all the balancing, alignments and new tires all the way around, I am still experiencing vibrations, what can it be?:rolleyes: The problem was first noticed last year when I had to have brake service and the tires were rotated, since then it has been vibrating. I thought all the new tires and alignment would fix it, but it didn't.

I need some help!

Thank you
How did you fix it? I have the same problem!!!

Sounds like the problem we are experiencing in our 2000 Bonneville se. We get constant vibe/shaking at 50mph, and then same at 70-75mph, however at that speed the problem comes and goes in a repeating cycle.New tires didn't solve it. Balancing didn't help. Put new half-shafts on and replaced one tie rod.This helped but didn't eliminate the problem.Still the same frustrating problem. :banghead: I'm beginning to think this is a tranny problem although ours shifts fine.Keep me informed and I'll do the same. Brian

I recently bought a '00 Bonneville SSEi and have noticed the SHAKES also. Seems most constant at 50-75 mph and can be felt by the driver and passengers. It is also felt in the accelerator pedal and steering wheel. The dealer I bought it from has balanced rotated and aligned. I'm still in the bickering stages with them as one of the conditions for buying this car was to "get rid if the vibration". I'll let you know ifn I get some satisfaction!