h2mach4

Low speed bounce & High speed shake?

I have a 1988 Chevy Celebrity. The front tires are only a month old, and the rear tires appear to be in good shape. At just 5 mph I can feel the car bobbing up & down. It smooths out a bit from 15-40 mph. Then at 45 and up the car is really shaking. The car holds a nice straight line though. The car acted like this before the new tires. I'd appreciate any advice.

Thanks,
AL

the_tow_guy

Since it happened before and after tire change, probably not wheel balance. Two likely candidates - front suspension shot (shocks/struts) or a front cv/axle. Had a bad cv axle on my Toyota a while back that drove me crazy until i figured out what it was; mostly heavy shakes about 45-50 mph. Can you feel the shaking through the steering wheel? Don't know if Celebritties are prone to either of those items failing or not; Joe will be a long for further info I'm sure.

mooser1

check for a bent wheel, this will also cause the exact symtoms you describe.....

danielmccoy

I had something similar on my Taurus and I replaced the front tie-rods and had it aligned and now it runs perfect.

the_tow_guy

h2, what did the old front tires look like that came off of it? Even wear across the tread and around or any uneven wear?

Joe_F

Swap the tires front to back.

If the problem goes away, it is wheel/tire related as mentioned here.

If not, then it is suspension/steering related.

h2mach4

Thank you very much for all the replys! I was surprised to get so many reponses. Tomorrow I'll check the items I can. Is it possible for me to check a CV joint? To answer the above questions:

1. No shaking in steering wheel (left to right). Just vibrating with the rest of the car.

2. Front tire wear was less in center, and more on the inside & outside edges. But I could be to blame due to low pressure?

Also, when slowing down, I can feel a pulsing in the brakes, which is right in sync with the bounce.

Thanks again,
AL

Joe_F

Pulsing in the brakes when you slow down is warped rotors.

They are cheap enough. Replace them with good quality US/Canadian made aftermarket parts and put good pads.

That should solve it.

the_tow_guy

Ah for the days of on-the-car spin balancing!

h2mach4

Thanks again for all the help. I'll let you know how it turns out.

Cheers,
AL

firstshift

Shaking similar to Celebrity

Gentleman:
Had similar problems to the Celebrity, noise, vibration at certains speeds, 'cept mine got worse at turnpike..(no pulsation on slowing down, though.)....Also hard right turn on the ramp make a rythmic thumping which probably meant CV joint. Turns out the axles I had replaced in July acc. to mechanic were both bad, one on driver's side had damaged seal into ATX. This after some months 6 months of procrastinating and incorrect fixes (tires, wheels, rotation). So far so good, right? With any luck store where I purchased axles will reimburse for labor as promised, though not happily...
Strange how both could be bad, though. Beats me, bottom line is vibration, tranny leak is gone. Watch them parts and save the paperwork!
Firstshift

h2mach4

Problem Solved

Although my rear tires looked good, the rear passenger side tire had developed a "bad spot." It finally gave way, and I had a blowout. The thump and vibration was gone, as soon as I put on the spare. Now I have new tires on the back, and it's smooth as can be Thanks again for all the input! Hope this experience can help someone else in the future?

Cheers,
AL