1998 S70 T5 auto - Noise from front left wheel/tire

babelfish · Post by **babelfish** » 07 Aug 2014, 08:40

I'm currently getting a noise from the front, driver's side wheel, but I can't seem to place it. It changes frequency with car speed, not engine speed, and, while the sound is tough to put into words, I'd describe it as a pretty subdued "tsch tsch tsch tsch" sound. Vaguely grindy in nature, but not very loud -- I can only hear it when the front driver's side window is down, and it gets tough to hear when there's no traffic. Obviously, having a curb to the left of my car, as on a one-way street, makes it louder, and then I can usually hear in in traffic.

I've checked for anything caught in the tire or brakes, and don't see anything. The sound started shortly after getting a new set of tires and wheels (Continental ExtremeContact DWS, 17" OEM Pegasus), but I don't see any uneven wear on the tire, though I've yet to take the wheel off the car. I'll try swapping the front/rear tires this weekend.

The sound doesn't really get louder at speed, might go away under braking pressure (tough to tell, really), and doesn't respond to the normal wheel bearing test of swerving like a maniac -- I can hear it regardless of which way I've got the car's weight going, as well as when I'm going straight, and the volume is the same regardless. I reckon the sound switches over from distinct noises to a continuous noise somewhere around 25mph, no higher than 30mph.

Given that the noise started shortly after new tires, they'd seem the obvious culprit. Aside from rotating the tires to rule that out, though, what else should I look at before I just take it into my mechanic? I found out back in June that my rotors are slightly warped, as they produced not insignificant vibration coming down a mountain pass, but I never really notice vibration under normal braking loads, so I'd be surprised if a warped rotor was catching and causing the noise.

Post by **rspi** » 07 Aug 2014, 09:08

Check the dust shield to make sure it isn't bent and touching the rotor. Could also be a bearing going bad.

babelfish · Post by **babelfish** » 07 Aug 2014, 16:39

Had a good, close look again. Found a little metal shared buried in the inside edge of some of the tread near the middle of the tire. Totally invisible from the outside, but I felt it, and managed to pop it out of the tread. It's small enough that I doubt it damaged the tire -- it felt like it was just embedded in the rubber -- and I'm not sure that it's the source of my noise, but I'll find out tonight/tomorrow morning if the noise is gone and report back.

babelfish · Post by **babelfish** » 08 Aug 2014, 08:15

Well, as expected, that bit of metal was not the source of my noise. I did notice a bit of brake-like squealing only when turning left yesterday, though, so I'm inclined to think there's something caught or that it's something else brake-related. My front brakes have had a very light squeal intermittently lately, and I just happen to have some spare front brake pads for my car, so I guess I'll install those over the weekend and see if I can spot any other issues at the same time.

babelfish · Post by **babelfish** » 29 Aug 2014, 08:41

Well, it's not very exciting, but for anyone who runs into this post in the future, the noise disappeared on its own, rather gradually, over the last couple of weeks, so it seems resolved for now. My guess is that I did, in fact, have a rock stuck under the caliper (I couldn't see anything when I inspected it last weekend, and I still heard the noise), or that the rotor was dragging on something, and in either case that the contact point ground itself down until the noise stopped.