Wh. Bearing OR CV Prob?

88911coupe · 01-22-2002, 12:23 PM

Car's in local P shop trying to diagnose problem. Car (88 Coupe 105k) has intermittent (but substantial) vibration above 50 mph that is WORSE when rt. side weighted and nearly absent when rt. side UNWEIGHTED. I suspect rt/rear wheel bearing (rt/fr bearing is 4 mos old) but...could bad CV's cause this? I ask b/c both CV boots torn. I plan to replace the boots on my own but extended warranty will cover wheel bearings.
Is the consensus that I am on the right track...shop seems confused.
As usual, thanks for the help,
Buck
88 Coupe

pbs911 · pbs911's Garage

Doe the vibration come through the steering wheel? I don't knwo how the CVs could cause the problem. Sounds more like a wheel bearing between those two choices. Did you attempt to rock the wheel when in wason the gound. You will get movement that you can actually hear if a wheel bearing is loose. It could also be that a wheel weight has fallen off, possibly an alignment issue, a worn suspension or brake componentonent, or even the tire has flat spotted. Did this happen all of a sudden of did you drive over a speedbump / pot hole lately? Has the car been parked for a long time?

AS for the torn CV boots, get them replaced and clean and lube them with new boots. You could be collecting all kinds of grime and dirt that will destroy the CVs. At the least, all the CV grease has been thrown out of the joints.

Sorry more questions than answers.

88911coupe · 01:21 PM

Thanks for the reply...the vibration has no effect on steering wheel or drivability, the cars tracks perfectly even during the vibration. It's as is the whole car is vibrating at highway speeds. Car is daily driver and this vibration seems to fade in and out over a period of days. Sounds more like a bearing than CV's but I have never had a CV go out so what do I know.
The problem has slowly grown worse over the last couple of months and only crops up about 15-20% of the time.
Thanks,
Buck

APKhaos · 01-22-2002, 02:36 PM

Buck,
Try to isolate the wheels/tires as as possible source.
If you have a second set, swap 'em. Borrow a spare set from a Dallas-based lister. Its quite surprising how random vibrations can be caused by a wheel or tire - even though no obvious event would point to them as a source. Just changed a CV/axle set on my 85 only to find the vibration got worse - it was a rear wheel.

Superman · 01-22-2002, 03:56 PM

Doesn't really sound like either. You need to deal with those CV joints ASAP. They may be junk already now that the boots are torn and dirt has been in there.

Worn CV joints click sometimes (more common on front wheel drive cars), and they can also shudder during acceleration or deceleration. But a vibration, not during hard acceleration, that shakes the whole car, well that doesn't sound like CV joints or wheel bearings.

Wheel bearings will nearly always make lots of noise for you to hear. Growling noise, dependent on wheel speed only, and not intermittent.

I'd switch wheels and tires if possible, I'd raise and inspect, and I might take the wheels to the tire shop to be checked for balance and trueness.