Hi there Car Talk Community! I have a 2006 Subaru Forester with 115K miles. It’s been well-maintained and well-loved.
For the past few months, the brakes have been inconsistently making a dragging/grinding noise when coming to a stop at low speeds (<5mph). It sounds to be coming from the front half of the car - I can feel it vibrating a little near the driver side. We’ve taken the car in to be looked at three times - each time, the mechanics think they’ve heard the noise and report there is absolutely nothing wrong with the brake pads or rotors. Twice they reported a shim was out of alignment. After the last shim adjustment, the noise got a little better - instead of grinding, it’s more of a dragging sound now. Because the noise is inconsistent, I haven’t been able to crack the formula of the conditions that produce it, other than that it only happens as I’m coming to a stop at very low speeds.
Is there something besides the brakes we should be having inspected? Does this sound safe to drive?
You could always turn the rotors and replace the pads any see if that stops the problem, pretty cheap experiment especially if you do it yourself and the worst that could happen is that you’d have new brakes! Other than that may want to see if there is a dust shield or something else near the rotor that may have bent or worked lose causing it to occasionally drag on the rotor. Other things that might be worth checking are suspension bushings, wheel bearings and CV joints.
We’ve had an exceptionally warm, dry summer here (Portland, OR), so I haven’t had the chance to experience the noise in wet weather (yet). It definitely occurs on dry days, and it doesn’t seem to matter if the car is warmed up or not. The noise is equally easy to hear when stopping on downhill and uphill slopes.
Just in case anyone is curious: I had an interesting conversation with a local mechanic who specializes in Subarus. He reports he recently encountered these same symptoms with a 2010 Forester, and they solved the problem by installing Subaru factory pads. Our brake pads were last replaced at Les Schwab, and they apparently use pads with metal compounds that don’t necessarily work well with Subaru rotors.
“they solved the problem by installing Subaru factory pads. Our brake pads were last replaced at Les Schwab, and they apparently use pads with metal compounds that don’t necessarily work well with Subaru rotors.”
While I can’t really explain it, I have observed multiple times over the years that Japanese vehicles tend to develop brake noise if any pads other than the OEM pads are used. I have observed this on both Toyotas and Hondas, so I wouldn’t be really surprised if the same held true with Subarus.
The noise doesn’t worry me as much as the vibration. Have them check the front suspension components, and if all is well, I agree with new pads and rotors as opposed to & cheaper than constant mental rumination.
Because of the age of the car, I’d suspect that you either have a caliper that is hanging up, or a brake hose that has begun to break down internally. The rubber hose breaks down internally and a small piece acts as a check valve each time you use the brakes. The fluid can pass this blockage and apply the brakes, but when you let off on the peddle the fluid hangs up and the caliper cannot release that particular brake.
Maybe there are several issues at play here. The vibration (if related to braking only) could be due to a slightly warped rotor or a rotor in which the parallelism is out. The usual limit is .002 of an inch and even that small amount can be felt by a mildly astute driver.
I’m kind of inclined to believe this shim adjustment bit you’re being told is a cover for they don’t know and won’t admit it so they resort to what a 3 piece jazz band might refer to as “improv”.
A groaning sound from the front of the car could also be due to something other than brakes. It could be a dry aged sway bushing, dry control arm bushing, strut spring groaning on a spring pad, etc.
Glazed brake pads and/or glazed rotors can also cause a groan; even with Subaru OEM pads.
Since “grinding” is also mentioned, I have seen Subaru brakes grind on cars that were near new and this was caused by environmental conditions; usually dampness in the air and most of the time this disappeared after X number of stops only to resurface again.
Grinding could also be caused by a loose heat shield on the exhaust as the engine changes its stance during braking.
Sorry for piling on here; just pointing out the what-ifs that could be involved.