Firebird V8-305 5.0L VIN E TBI (1989)
Power Steering Fluid: Customer Interest
Power Steering - Reduced Assist At Low Temperatures
Bulletin Number:
91-3-12
Reference Number:
033206R
Publish Date:
2/91
Subject:
REDUCED POWER STEERING ASSIST AT LOW AMBIENT TEMPERATURES (NEW POWER STEERING FLUID)
Models
Affected:
1980-1991 ALL MODELS
Applications:
Appropriate for all passenger vehicles, but particularly beneficial in 1980 and later FWD Models equipped with Power Rack and Pinion Steering.
CONDITION
Comments of reduced power steering assist at low ambient temperatures (approximately 10 degrees Fahrenheit and lower) may be noted by some vehicle
operators when turning the steering wheel in BOTH the right and left direction during warm-up after cold start. All vehicles with power steering exhibit
this condition to varying degrees, but the condition may be more noticeable with power rack and pinion steering systems that typically have longer hoses
and cooler lines.
Note:
This condition, which is related to power steering fluid viscosity, should not however be confused with conditions having similar
symptoms such as that described in Pontiac Technical Service Bulletin 88-SM-10, related to internal steering gear fluid by-pass.
CAUSE:
In cold weather, power steering fluid thickens in the same manner as any other petroleum-based oil or fluid. Upon cold starting, the fluid resists
movement through the system and the driver senses reduced power assist (sometimes referred to as "stiff steer"). As the vehicle operates and fluid
circulates through the power steering system, the fluid warms and thins to its normal operating viscosity.
CORRECTION:
Saginaw Division has developed a new Low Temperature Climate Service Fluid for use in cold climates. Compared with conventional power steering
fluid, this new fluid flows better at low temperatures and resists the thickening which contributes to reduced power assist upon start up.
RACK AND PINION STEERING SYSTEMS
Reduced power assist upon cold weather starting may be more noticeable in Power Rack and Pinion steering systems that may contain six or more feet of
pressure and return hose along with long cooler lines. Such long systems contain greater volumes of fluid and vehicles so equipped tend to have longer
periods of reduced power assist. The new fluid performs particularly well with current designed Rack and Pinion steering systems and special
remanufactured Rack and Pinion Steering Assemblies.
PARTS INFORMATION:
Low Temperature Climate Service Fluid is available from GMSPO. Order as:
Container Size
Part Number
16 ounce
12345866
32 ounce
12345867
Parts are currently available from GMSPO.
SERVICE PROCEDURE:
The power steering fluid replacement procedure is a two-stage process:
first, flushing the old fluid from the system with new fluid; and second, bleeding the system to remove any trapped air. The following two sequences
outline the steps in each procedure.
FLUSHING THE POWER STEERING SYSTEM
1.
Raise the front end of the vehicle off the ground until the wheels are free to turn.