Same reason for both. The pad is not squeezed as tightly to the rotor as it may seem, even with the pedal pressed hard. If it were then the brake pad & rotor would be locked together with no slippage at all & the wheels would be locked up.
Consider applying your brakes a controlled slide with the friction between the rotor & pads varying with the pressure you apply. The rotor is traveling under the pads at a very high rate of speed. The surface of the pad & the rotor are uneven. An high frequency oscillation sets up in the pads but the vibration is less than 0.001" The noise you hear is the oscillation (the squeal). Thw "magic goo"mentioned earlier lightly bonds the brake pads to the calipers & helps prevent the oscillation (the squeal). Tom Hargrave www.kegkits.com ----Original Message---- From: Allan Streib <[EMAIL PROTECTED]> Sent: 02/21/07 02:39 PM To: Mercedes Discussion List <[email protected]> Subject: Re: [MBZ] Brake Squeal and other topics -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= "Tom Hargrave" <[EMAIL PROTECTED]> writes: > Brake squeal is caused by the brake pads vibrating at high > frequency. How can the pads be vibrating when they're being squeezed against the rotor? Why do drum brakes squeal too? Allan -- 1983 300D 1966 230 _______________________________________ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
