Suburban 1/2 Ton 4WD V8-350 5.7L (1986)
Fluid Pressure Sensor/Switch: Customer Interest
A/T - Buzzing Noise at Idle
BULLETIN NUMBER:
93-7A-18
SECTION:
7A
NUMBER:
4
CORPORATE
REFERENCE NUMBER:
277142
DATE:
October 1992
SUBJECT:
BUZZING NOISE AT IDLE (INSTALL NEW PRESSURE REGULATOR VALVE)
MODELS:
1982-93 C/K, R/V, S/T TRUCKS AND G/M/L VANS WITH 4L60 TRANSMISSIONS
CONDITION:
Some 1982-93 vehicles equipped with a HYDRA-MATIC 4L60 transmission may have a buzzing noise coming from the transmission when the vehicle
is at idle. The buzzing noise may be noticed more when the vehicle is in reverse at idle.
CAUSE:
The buzzing noise may be a result of pressure regulator valve oscillating due to oil pressure instability at lower idle RPM.
CORRECTION: