Brake grinding from left front brake, pads/rotors good

shinyhappyzealot · 01-16-2013, 01:22 PM

I'm having low speed grinding that sounds like it's coming from the left front wheel/brake when I'm first starting out or when applying the brakes at low speed. I don't experience this when I'm at freeway speeds at all. Both pads and rotors are in good condition. It sounds exactly like worn pads grinding on rotors, but that's not it. Doesn't sound like brake dust squeal either. Any suggestions of other things to check before I ask the mechanic to investigate?

2000 Insight, MT, 300k miles, pads/rotors replaced and in good condition.

Could this be a sticking caliper? They are original.

Thanks

AbCaRed00 · 01-16-2013, 02:03 PM

A rock stuck by the backing plate? Does it occur backing up?

I just say that because of the potential for road sand and pebbles this time of year and I once had that last spring.

shinyhappyzealot · 01-16-2013, 02:43 PM

Quote:

Originally Posted by AbCaRed00

A rock stuck by the backing plate? Does it occur backing up?

I just say that because of the potential for road sand and pebbles this time of year and I once had that last spring.

yes, same sound in reverse.

AbCaRed00 · 01-16-2013, 03:44 PM

Quote:

Originally Posted by shinyhappyzealot

yes, same sound in reverse.

Could just be a rock trapped somehow which will eventually wear down... for rocks i've tried backing and braking, multiple fwd<>rev motions and the car-wash sprayer used on occasion.

If more than a rock, if you can get that wheel in the air, give it a spin and a shake to check for vibrations and remove the wheel to see better; the caliper could be stuck too as you say, maybe just needs cleaned up as a d-i-y job for both sides vs. mechanic.

TopFuelTim · 01-17-2013, 06:49 AM

FWIW, I could hear the front disc brake noise like a light grinding in both of my MT cars. Both have pads and rotors in pretty good condition. Have to wait on the CVT my daughter uses to come home so I can listen to its pads, but my friend's CVT that is currently at my house has quiet front discs.

My 0.02 worth,
Tim Glover

talonmike · 01-17-2013, 08:29 AM

It could also be the bearing end play.

**AClewell** · 01-17-2013, 12:09 PM

I have had to replace the front wheel bearing (hub assembly) on the front of my 01 a couple times. The noise starts out like yours and gradually gets worse over hundreds of miles. You will begin to notice it at freeway speeds as it gets worse if it's the bearings.

The part is less than $100 at a parts store but you will need a press to get the hub itself out of the bearing assembly. The outer bearings inner race is a pain to get off. I always end up carefully cutting the race with a torch to get it off.

Hopefully your car just has a rock stuck but if not I hope I was some help.

Alan

Minnsighter · 01-20-2013, 03:38 PM

Good luck. I am having a similar grinding sound at low speeds, but it appears to be coming from the rear. I was assuming I have a warn shoe grinding on my drum, and assumed rear drums would be cheap since they're so small. I got on our forum to see if I could find any rear bearing assembly diagrams - so I can be sure I am getting the right parts. Since I will have it apart, I should replace the bearings. On a really cold morning, I can tell that the bearing grease is stiff when I back out of my garage. I would like to replace the rear bearings and pack them w/ some silicone grease, if that's possible. I'm on my way to Napa Auto to see how much rotors and shoes are. I've got 115k on it now. I figured I was way overdue for rear shoes, but after reading some comments in this post, I am now hoping it is just brakes and not a bearing somewhere. Maybe the stiffness I feel on the cold mornings is due to a bearing going out. Not the end of the world if they're easy to replace. I hope the drums aren't too expensive.

Minnsighter · 01-20-2013, 03:41 PM

My brakes are not loud, but they're not quiet. My assumption was the Insight has light noise insulation in order to keep weight down, so I am hearing more brake noise than I am accustomed to hearing in a car. Is it possible a CVT Insight has more noise insulation due to a louder transmission? (I have no idea if the CVT trans is louder than a MT trans, just a plausable explanation for quiet brakes on the CVT).

shinyhappyzealot · 01-20-2013, 03:44 PM

had a mechanic take a look at it and the driver's side caliper is sticking and wore down the inner pad. he's recommending a full rebuild of both sides - calipers, pads, rotors, brake lines, which isn't cheap. at 300k miles and driving on gas only with a dead IMA, i'm on the fence with the car. i'm going to bring it home and see if the rotor is scored. while replacing brake parts piece-meal is not wise, i might try putting on a more aggressive pad on both sides and just replace the caliper and flush the whole system. i'll find out whether it pulls when i'm bedding in the new pads.

thanks everyone for the help.