ATI99141503

Advanced Technical Information
Clicking Noise From Front PCCB Rotors
4
911 (991)
1503 4651
This bulletin replaces bulletin Group 4,
#1503, dated 8-25-15
Vehicle Type:
911 Turbo S (991)
Model Year:
2014 to Present
Information:
PCCB Rotors may be making a clicking type noise
Work Procedure:
Some customers have reported a clicking noise from their vehicle at slow speeds.
NOTE: The clicking noise in no way impairs the performance or safety of the braking system. The
customer may continue to drive the vehicle without restriction. The clicking noise does not constitute
a defect.
NOTE: Due to the customer sensitivity of this issue, please submit a TLAR from the
beginning of the issue.
Due to tolerances on some of the parts connecting the brake disc to the mounting plate, small
relative movements between these parts can occur. As a result, a clicking noise can be heard when
the brakes are applied at low speeds.
The 991-II rotors have a slightly different design for the attachment of the rotor hat to the disc (Starting in MY 2017). These rotors are retrofittable on the 991 generation I vehicles.
Pre Checks
Wheels - Before rotors are replaced, it is necessary to check the mating surface of the wheels with a
straight edge (12” Starrett 380) to insure flatness of the surface. Imperfections in the surface may
have an influence on the rotor and cause noise.
©2016 Porsche Cars North America, Inc.
AfterSales
Apr 1, 2016
Page 1 of 3
4
911 (991)
4651
1503
Advanced Technical Information
It is necessary to check for flatness in about 6 different positions around the mating surface (roughly
every 60°), it is ok to do more than that, but not less.
The mating surfaces at the outer and inner areas of the mounting circle need to be checked for
flatness. The recessed area in between (photo below) is not a part of the measurement.
Measure here
Not here
Use a feeler gauge that is very thin. The .05mm thickness is probably going to be necessary to find
the uneven areas.
Record all measurements; make sure to include photos in PQIS.
Apr 1, 2016
Page 2 of 3
AfterSales
©2016 Porsche Cars North America, Inc.
4
911 (991)
1503 4651
Advanced Technical Information
Center locking wheel bolt - Insure that the center locking wheel bolt is properly lubricated in accordance with WM 440519.
Insure that all mating surfaces are clean and free of debris.
When torquing the wheel bolts, make sure the vehicle is off the ground. Use a torque wrench
(that is properly calibrated) in one sweeping motion, not an intermittent jerky motion.
Rotors – The new rotor part numbers are listed below. They are also in PET.
991- II rotor part numbers:
Front Left Rotor: 991.351.407.06
Front Right Rotor 991.351.408.06
Rear Left Rotor: 991.352.409.07
Rear Right Rotor: 991.352.410.07
NOTE: Due to small design changes, 991- II rotors may not be an identical visual match to 991- I
rotors. This is considered normal and does not constitute a defect in workmanship or justify
replacement.
Reference:
Dealership
Distribution
Routing
465119 Removing and installing front PCCB brake disc.
Service Manager
________
Shop Foreman
________
Service Technician
________
________
________
________
Asst. Manager
________
Warranty Admin.
________
Service Technician
________
________
________
________
Dr. Ing. h.c. F. Porsche AG is the owner of numerous trademarks, both registered and unregistered, including without limitation the Porsche Crest®, Porsche®, Boxster®, Carrera®, Cayenne®, Cayman®,
Macan®, Panamera®, Speedster®, Spyder®, 918 Spyder®, Tiptronic®, VarioCam®, PCM®, PDK®, 911®, RS®, 4S®, FOUR, UNCOMPROMISED®, and the model numbers and thedistinctive shapes of the
Porsche automobiles such as, the federally registered 911 and Boxster automobiles. The third party trademarks contained herein are the properties of their respective owners. Porsche Cars North America, Inc.
believes the specifications to be correct at the time of printing. Specifications, performance standards, standard equipment, options, and other elements shown are subject to change without notice. Some options may be unavailable when a car is built. Some vehicles may be shown with non-U.S. equipment. The information contained herein is for internal authorized Porsche dealer use only and cannot be copied or
distributed. Porsche recommends seat belt usage and observance of traffic laws at all times.
©2016 Porsche Cars North America, Inc.
AfterSales
Apr 1, 2016
Page 3 of 3