Maxima GXE V6-3.0L (VQ30DE) (1999)
Technical Service Bulletin # 94-012A
Date: 990617
Brakes - Judder/Steering Wheel Shimmy
Classification:
BR94-002a
Reference:
NTB94-012a
Date:
June 17, 1999
This amended version of NTB94-012 adds a caution and a note to the service procedure. Please discard all paper copies of NTB94-012.
This bulletin supersedes TS89-105/BR89-004
APPLIED VEHICLE(S):
ALL
BRAKE JUDDER/STEERING WHEEL SHIMMY
SERVICE INFORMATION
Brake judder/steering wheel shimmy is a condition which may occur in any vehicle when excessive rotor thickness variation is present on one (1) or
more of the vehicle's brake rotors.
Rotor Thickness Variation (RTV) is the variation in thickness around the rotor. The RTV can be determined by measuring the rotor thickness with a
micrometer at several locations around the circumference of the rotor. The RTV is the difference in a thickness between the thickest and thinnest points
on the rotor.
Rotor Run-Out is the distance that the rotor surface travels in and out, in relation to the vertical plane of the hub, as the rotor turns with the hub. The
distance is measured with a dial indicator.
NOTE:
Rotor Run-Out does not cause brake judder or steering wheel shimmy. However, excessive Rotor Run-Out does lead to rotor thickness variation as
the rotor wears. It is the excessive rotor thickness variation that causes judder and/or steering wheel shimmy. This is described in more detail below.