LeSabre V6-181 3.0L (1986)
Brake Rotor/Disc: Customer Interest
Brake - Pulsation Causes/Cures
Bulletin
86-5-7
Date
Apr. 86
Ref. No.
86-112-5
SUBJECT:
BRAKE PULSATIONS
MODELS AFFECTED:
ALL MODELS
Brake pulsations are normally the result of uneven rotor thickness or an out of round condition in a brake drum. Pulsations can also be caused by a rust
build up on the rotor. Under certain conditions, the exterior of the rotor may rust. This would normally not occur unless the vehicle was parked for a few
days and corrosive conditions were present. If the rotor exterior does rust, the area under the brake pads usually remains rust free. The difference in
friction between the rusted and unrusted areas can cause pulsation for several stops, but will improve as the linings scrub the rust off the rotor. Normally,
two or three stops will return the system to normal. Under adverse rust conditions, as many as five or six stops may be required. Usually this condition
will correct itself. It is, however, important that the customer understand what is happening should you receive a comment of this condition.
