Brake Noise
 

I replaced the front and rear pads on my wife's 99 ML 320 a couple of months ago. I used Mintex pads (from Phil) for both front and rear. There was no noise at first. Now, it has developed a squeal upon moderate braking. I can't tell if it is coming from the front or rear.

1) Any tips to determine if the noise is coming from the front, rear, or both?

I applied anti-squeal brake grease between the pads and caliper everywhere it looked like the two surfaces met.

2) Are there any secrets to where you apply the grease?

I did not have the rotors turned. I did drive it several miles with the intent of bedding the new pads to the old rotor surface. (Made some very gentle stops. Then purposely rode the brakes very lightly for a while. Gradually made some moderate stops. After a few days of normal driving, purposely did some hard stops.)

3) Anything else you can suggest (other than cranking the radio louder)?

TIA

There is a spray you can use.
It's called " Disc Brake Quiet ", available at any automotive supply store.
You spray it on the backing plates of the pads, let it sit for 10 - 15 minutes and re-install the pads. ;)
I assume your new pads already have a chamfer on the edges?

Thanks, Manny. I'll give it a try.

I'm not sure about the chamfer. Would that have been on them from the factory or is it a pattern that is supposed to wear into the pad??? I'll let you know after I R&R them (which won't be this weekend).

In the meantime, any other tips are appreciated.

sunedog, use Textar brake pads next time. I've never had a squealing problem with them.

I have tried many pads on all my cars. S320, clk430 and S500. Always squeaked, except when you buy the factory pads. They are made of softer material. Yes more dust but no squeaks or squealing. Also mercedes mechanics use a grey grease that is sold at parts counter which is applied to pad. This really helps.

Good luck.

Thanks everyone. I rephad Mintex pads on the front and Brembo's on the rear. I was happy with both sets and intended to replace them with the same brands. But when I talked to Phil, he advised he was carrying Mintex rear pads this time so I went with them.

I also bought gray anti squeal brake grease from Phil. I applied it everywhere it looked like pieces contacted.

I've run Mintex before & really liked them.
Most squealing is caused by high frequency vibrations between the pads & the caliper.
Suggest you try what I said earlier. ;)

Follow up. I finally had a chance to try the Disk Brake Quiet product and it worked. Thanks to everyone and especially Manny.

I believe the chamfer is on the front edge of each brake pad and lets you know how to install them.