For 1990-2009 cars

# Front Brake Noise and/or Front Brake Pulsation

Subject: | Front Brake Noise and/or Front Brake Pulsation (Replace with New Front Disc Brake Pads) - Technical bulletin 96-T-40 was revised prior to distribution due to changes in the SUBJECT, and the addition of a CONDITION, CAUSE and CORRECTION.

Models: | 1991-1997 Saturns

### Condition

Repeat excessive front brake grind/growl, squeak/squeal noise and/or pulsation during slow braking.

IMPORTANT: Never replace disc brake pads on one side of axle only. Left and right side disc brake pads must be replaced as axle sets.

### Cause

Brake noises may be caused by vibration of brake components and/or contact between the disc brake pad and rotor during stopping. Some intermittent brake noises are normal. The disc brake pads (P/N 21012690) used on 1991-1996 Saturns can allow some front brake noise.

In high corrosion areas of the country, semi-metallic pads, interacting with the front rotor, may contribute to the corrosion process leaving a front disc brake pad shaped "footprint" on the rotor. This "footprint" may cause front brake pulsation.

In addition, pulsation may be caused by thickness variation worn into the rotor by the disc brake pad. The new disc brakes pads, installed on 1997 vehicles, cause less rotor thickness variation as a result of wear.

### Correction

Replace front disc brake pads with new non-asbestos organic front brake pads (P/N 21012856) used on 1997 vehicles. Brake rotors should not be refinished unless there is a pulsation caused by the rotor, or the brake rotors are excessively scored. Scoring of brake rotor surfaces not exceeding 1.5 mm (0.060 in.) in depth, which may result from normal use is not detrimental to brake operation.

All 1997 Saturns are built with the new non-asbestos organic front disc brake pads (P/N 21012856) and new front brake rotors (P/N 21012880). When servicing a 1997 vehicle, use the new design front disc brake pads and new design front disc brake rotors.

### Front Disc Brake Pads (P/N 21012856)

The new front disc brake pads (P/N 21012856) can be identified by the friction material being slotted into two sections, similar to the rear disc brake pads currently being used on Saturn vehicles. The new design front disc brake pads (P/N 21012856) can be used with either the previous or new design front brake rotors, whether either rotor is new, used, refinished or different design version on either axle.

Important: Never replace brake pads on one side of axle only. Left and right side brake pads must be replaced as axle sets.

### New Front Brake Rotors (P/N 21012880)

The new design front brake rotors (P/N 21012880) can be identified by casting numbers 18022049 or 18022050, located on the inboard side front brake rotor. (The casting number for the previous design front brake rotor is 18013721.)

Important: The new design front brake rotors should not be used with the previous design front disc brake pads (P/N 21012690). All 1997 vehicles, and any past model vehicle that has a front brake rotor replaced with the new design front disc brake rotor (P/N 21012880), should utilize the new front disc brake pads (P/N 21012856). Using the new design front brake rotors with the previous design front disc brake pads (P/N 21012690) may result in objectionable brake noise.

### Parts Information

Part Number | Description | Usage
--- | --- | ---
21012690 | Pads-Front Disc Brake | 1991-1996* (NOTE: Should be used with front disc brake rotors 21012664.)
21012856 | Pads-Front Disc Brake | 1991-1997
21012664 | Rotor-Front Brake | 1991-1996
21012880 | Rotor-Front Brake | 1991-1997 (NOTE: Should be used with front disc brake rotors 21012856.)

* If vehicle does not exhibit repeated, excessive front brake grind/growl, squeak/squeal Noise or pulsation during slow speed braking.