drwafk

2010 Lexus IS350 lowered 2.0 inches on BC Racing Coils (1 year old). Brake pads (all around) are 1 year old. Car has 72,000 miles.

Problem: When putting the car in drive and creeping forward at 5 mph then applying the brakes I hear a single metal pop sound. The sound goes away after successive brake applications while moving forward. I stop the car and put into reverse, roll backwards then apply the brakes and hear the sound again. Sound goes away after successive applications unless I tap the brake every 1-2 seconds. Turning the wheel left or right has no effect on the matter, its a fore and aft situation.

Troubleshooting so far: Wheels off, brake pads removed and inspected. All suspension nuts/bolts honked down to include the top and bottom of the coils.

Question: Can someone confirm if the rotors are supposed to spin freely around the hub where the bolts stick through? There's a little slop there but I think that's normal.

Suspects: Pads a hair too small. Eng/Transmission mount? Sway bar clicking because of weight loading/unloading?

Any help is greatly appreciated.

Yes I know how to use the search function but no dice. Sound problems are often vague and unique. Thanks again.

redspencer

iTrader: (1)

Perhaps the pads are shifting a bit under light braking when coming to a stop?

I very recently had an issue like this when I would apply the brakes at very low speeds and I would hear a light knock/click sound coming from the wheelwell. After I pulled out the pads and applied some CRC Disc Brake Quiet to the shims (as well as cleaning out debris stuck in my dust shield), the noise went away. Hopefully this might be what you're experiencing as well.

2KHarrier

Completely different car, but I had the very same issue on my Son's GMC Sonoma. Turn's out one of the caliper bolts backed out and fell off, leaving only one bolt to secure the caliper in place. As we drove forward, the caliper would move just enough to tap against the hat on the rotor, but you would stop and look at it and never see a problem.. It took me a while, but I finally figured it out...

So maybe check all your hardware?

Gville350

iTrader: (10)

AWD or RWD model?

drwafk

Thanks for your inputs. I suspected the brake pads but was in denial as it just didnt seem like it was the cause. I picked up some CRC disc brake quiet, cleaned all the parts and put it back together. The sound went away...kind of. I think the sound is either more sublte or coming from the rear brakes now. I'll clean those up this evening and report back. Either way, thank you.


I did check all the nuts/bolts on the suspension, calipers, etc.. Thanks.

drwafk

RWD. Funny you ask that because now I'm hearing what sounds like the compressing of bushings...a squeegie sound if that makes sense when I stand on the brakes and go from Park to Drive.