Chasing Ghosts

Time to get the car back on the lift.
New wheel bearings set us back about $40. We also replaced the seals, adding just a few more bucks to the tally.
A press helped install the new races.
Ta-da, a new wheel bearing. It didn't solve the noise, however.
While the car was in the air, we noticed a torn tie rod boot. Looks like we'll be upgrading to Turbo pieces sooner than expected.
New bearings didn't chase away the noise. Was it the tires? Swapping tires from another 911 provided the answer.

Out went the old bearings, in went the new ones.

We recently picked up a hmmmmm at around 35 mph, and the right-front wheel had a bit of play to it. Tightening up that bearing seemed to make the noise a bit louder, so we ordered new wheel bearings.

Out went the old bearings, in went the new ones. Guess what? The noise was still there.

So now the diagnostic work could begin. Were we just noticing some tire hum? Maybe. We swapped over some front tires from another 911. Guess what? No more noise.

Either way, between the color of the grease—pretty dirty—and the brand of manufacturer, we think the old bearings were the originals. For $40 or so in parts, servicing them was probably prudent.

Join Free Join our community to easily find more project updates.
View comments on the CMS forums
iceracer PowerDork
6/28/10 5:44 p.m.

I have had strange vibrations in my Liberty. All kinds of things were no help. Just replaced the worn out Goodyears with Yokohamas and the vibrations are gone.

David S. Wallens
David S. Wallens Editorial Director
6/28/10 7:57 p.m.

Cool. These tires are fairly new, but I'd swear that the noise recently showed up. It's not bad--just a hum between 30 and 35 mph or so. I was more concerned that we had a major problem.

7/2/10 2:35 p.m.

I see the 911 has picked up a ducktail. What's the story behind that?


stylngle2003 New Reader
7/3/10 10:14 p.m.

story starts here

Cotton UltraDork
7/7/10 9:58 a.m.

My 85 911 had a similar hum....kind of like running your finger around the top of a glass. I turned the rear rotors and the problem was solved. Talked to a Porsche mechanic and he said he'd seen that a lot over the years on AC 911s.

bearmotorsports New Reader
7/9/10 8:52 a.m.

Tire related problems are mostly to blame for these kind of Hummms or other. This has happened many timesvwhen customers complained of road noise. Tires wear in a funny way at times.

Sponsored by


Our Preferred Partners