High Pitched noise from rear passenger wheel at 25+mph


#1

Hi everyone. I have a 2003 Porsche Boxster 986 base model. Yes, I bought a used older German sports car… I know. It is a fun car, it really is, but does need help from time to time… and I’m learning a lot about car repairs and maintenance in the process! I’m thinking about bringing it to a local indy for diagnosis, but I was hoping the internet could maybe give me an opinion first.

So, the car is making a high pitched sound that seems to be coming from the rear wheel. I can hear it when driving above 25mph or so - it reverberates off of walls and is less pronounced but still audible at speed without a wall present. It’s pretty steady when moving about 25 or above, but seems to go away below that speed and it seems to be consistent in tone regardless of speed (above 25). I’m guessing it’s a wheel bearing, but maybe you can help confirm my suspicion or have some other ideas?

I jacked the car up and checked for play in the rear wheels and didn’t find anything. I also rotated the wheels and they seemed to rotate smoothly with only a little friction from the brake calipers (which I believe is normal). It doesn’t sound like the typical bad bearing sound which seems to be more of a growl.

Here’s a link to the sound if this board allows such things:

wheel noise

Appreciate any suggestions. Thanks so much!


#2

Check your brake pads first.Are they worned to the point the pad wear indicator is warning you to replace them. .Are they wearing evenly?Does the noise stops when pressing on the brake pedal?Does this wheel feel hotter than the other wheels after a short drive? I had a similar noise on my Corolla and it turned out to be a seizing caliper. Here it is


#3

Thanks Corrolaguy! That sound is indeed very much like what I’m hearing. I’ll take the caliper off and take a closer look. Did you have to replace your caliper?

edit: also, I did look at the pads and they have plenty of material left - I didn’t look very closely, so maybe the wear is uneven. The wheel doesn’t seem hot after a drive and braking doesn’t seem to effect the sound… which is weird and what lead me to think it’s something other than the brakes. I’ll take the pads off and have a closer look.


#4

Yes, I had to replace the caliper.The caliper was 19 year old

If you live in an area where they use road salt (rust belt) it is not unusual for a caliper piston to get stucked in its bore.You need to verify that the rubber seal around the piston is intact with no nicks,cuts etc.

Does your car have a drum style e-brake in the rear?It could be an accumulation of dust inside the drum housing.Use some aerosol brake cleaner and clean the entire brake assembly.See how it goes and please report back.


#5

The car does have a drum style e-brake in the rear. I’ll clean the e-brake as advised and check the calipers and report back. I should be able to work on it tomorrow but may have to wait until later in the week. Thanks so much for the advice!


#6

Just to update. I took the easy route for now. Someone suggested on another board that I power wash the brakes as brake dust can accumulate in the caliper. I did, and the sound is mostly gone. It comes back intermittently, so I’ll have to take the caliper off and check things out. I’ll update the thread when it’s fully fixed. Thanks again for the direction, it’s really good to have the problem narrowed down and that I don’t need to replace the bearing!


#7

Sounds like you are on the right track. The way wheel bearing noises are most commonly reported here is “a roaring sound that gets louder the faster you go”. Sort of like the sound you hear when driving on a pavement that has a very rough surface, like when the road repair crew roughens up the surface with a big grinding machine before they repave.