PIT4907A

Bulletin No.: PIT4907A
Date: Nov-2012
Subject:
Normal Characteristic - Gray Coating On Brake Rotors
Models:
2002 - 2013 GM Passenger Cars and Light Duty Trucks
This PI was superseded to update model years. Please discard PIT4907.
Condition/Concern
Questions continue to be received on the removal of the brake rotor gray coating. The gray coated rotors can be found on both new vehicles and replacement
parts from GM SPO. The rotors are coated with a zinc organic protective spray to prevent the rotors from rusting before they go into service.
Recommendation/Instructions
The coating should not be removed and will wear off with normal brake usage. The coating does not hinder brake performance.
Note: The coating may need to be removed from the rotor's hub mating surface if there is excessive rotor Lateral Run Out (LRO) when assembled.
Customer Information
Please communicate to the customer this condition is a normal operating characteristic of their vehicle. It will not impact the designed performance or reliability
of the vehicle.
Please share this information with the customer, including a copy of this message.
GM bulletins are intended for use by professional technicians, NOT a "do-it-yourselfer". They are written to inform these technicians of conditions that may
occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools,
safety instructions, and know-how to do a job properly and safely. If a condition is described, DO NOT assume that the bulletin applies to your vehicle, or that
your vehicle will have that condition. See your GM dealer for information on whether your vehicle may benefit from the information.
WE SUPPORT VOLUNTARY TECHNICIAN CERTIFICATION
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