Chevrolet 1980 Light Duty Truck Service Manual page 274

3C-6 FRONT SUSPENSION
Probable Cause
LEAF TYPE REAR SPRING
a. Rear leaf spring broken
b. Bent rear axle housing
c. Frame or underbody out of alignment
COIL TYPE REAR SPRING
a. Damaged rear suspension arm and/or worn bushings
b. Frame out ot alignment
c. Bent rear axle housing
a. Steering column alignment
b. Steering linkage needs lubrication
c. Idler arm bushing worn
d. Steering gear adjustment
e. Power steering gear valve spool binding
f. Obstruction within power steering gear
g- Improper caster setting (negative)
a. Low or uneven tire pressure
b. Front wheel bearing incorrectly adjusted
c. Brakes incorrectly or unevenly adjusted
d. Front spring sagged
e. Steering gear off high point
f. Incorrect or uneven caster
g- Leaking wheel cylinders
Special Suspension Equipment
Check Service Parts Identification Sticker for any
special suspension equipment; such as, a heavy duty
suspension. Vehicles equipped with this type of option have
a somewhat stiffer or harsh ride, and this should be kept
in mind during the following tests. If complaint about
stiffness should occur while vehicle is still new (under 5,000
miles) (8 000 km), owner should be advised to have ride
" D O G " T R A C K IN G
R E T U R N A B IL IT Y POOR
E R R A T IC S T E E R IN G ON B R A K E A P P LIC A T IO N
Fig. 3C-6-Front Suspension Diagnosis Chart C
Probable Remedy
a. Replace spring
b. Replace housing
c. Align frame
a. Replace suspension arm and/or bushings
b. Align frame
c. Replace housing
a. See Section 3bin shop manual for proper alignment
b. Lubricate chassis
c. Replace idler arm
d. Adjust gear as outlined in Section3bof shop manual
e. See Section3bin shop manual
f. See Section3bin shop manual
g- Check and reset if necessary
a. Inflate tires to proper recommended pressure
b. Adjust bearing as necessary
c. Adjust brakes as necessary
d. Check shop manual for proper riding heights and
replace spring if necessary
e. Check and correct steering if necessary
f. Check and adjust caster as necessary
g- Replace (See sec. 5)
rechecked after 7,000 to 8,000 miles (11 200 to 12 800 km).
Vehicle Load Conditions
Note any exceptional load conditions under which the
owner normally operates the vehicle; such as, large tool
boxes full of tools, pick up bed full etc. If exceptional loading
is apparent, check the distribution of this weight. Note if
it is all toward one side of the vehicle or at the extreme rear
of the vehicle. Reposition load as required to obtain a more
uniform weight distribution.