ST_330_72_1972_Chevrolet_Truck_Chassis_Service_Manual_10_to_30

STEERING 9-2 3. Loosen the steering gear adjuster plug locknut and
back the adjuster plug off 1/4 turn (fig. 2).
Fig. 1—Removing Pitman Arm — Typical
4. Remove the horn button cap.
Steering Gear
Before any adjustm ents are made to the steering gear 5. Turn the steerin g wheel gently in one direction until
stopped by the gear; then turn back one-half turn.
attem pt to c o rre c t com plaints of loose or h ard steering,
or other wheel disturbances, a careful check should be CAUTION: Do not tu rn the steerin g wheel hard
made of front end alignm ent, shock a b so rb ers, wheel against the stops when the steering linkage is
balance and tire pressure for possible cause. disconnected from the gear as damage to the
ball guides could result.
C orrect adjustment of steering gear is very important.
While th e re are but two adjustm ents to be made, the 6. M easure and reco rd "bearing drag" by applying a
following procedure m ust be followed step-by-step in the torque wrench with a 3/4 inch socket on the steering
o rd er given. wheel nut and rotating through a 90° a rc (fig. 3).

1. D isconnect the b attery ground cable. NOTE: Do not use a torque wrench having a
2. Remove the pitm an arm nut. Mark the relationship of maximum torque reading of m ore than 50 inch
pounds.
the pitman arm to the pitman shaft. Remove the
pitm an arm with Tool J-6632 or J-5504 as shown in 7. Adjust "th ru st bearing preload" by tightening the
F igure 1. adjuster plug until the proper "thrust loading p re­
load" is obtained (See specifications section at re a r
of this manual). When the proper preload has been
obtained, tighten the adjuster plug locknut to speci­
fications and recheck torque. If the gear feels
"lumpy" after adjustment, there is probably damage
in the bearings due to severe impact or im proper
adjustment; the gear must be disassem bled for re ­
placem ent of damaged p a rts.

8. Adjust "over-center preload" as follows:
a. Turn the steering wheel gently from one stop all
the way to the other carefully counting the total
num ber of tu rn s. Turn the wheel back exactly
half-way, to center position.
b. Turn the lash adjuster screw clockwise to take
out all lash between the ball nut and pitman shaft
secto r teeth and then tighten the locknut.
c. Check the torque at the steerin g wheel, taking the
highest reading as the wheel is turned through
center position. See the Specifications Section
for proper over-center preload.
d. If necessary , loosen locknut and read ju st lash
adjuster screw to obtain proper torque. Tighten
the locknut to specifications and again check to r­
que reading through center of travel.

Fig. 3—Checking Torque at Steering W heel

10-30 CHEVROLET TRUCK SERVICE MANUAL

STEERING 9-3

NOTE: If maximum specification is exceeded, Fig. 5—Steering Column Lower Bearing Adjustment
turn lash adjuster screw counter-clockwise, then
come up on adjustm ent by turning the adjuster 1. Set wheels in straight ahead position by driving
in a clockwise motion. vehicle a short distance.

9. R eassem ble the pitm an arm to the pitm an shaft, 2. Note stee rin g wheel position. If off m ore than 1 inch
lining up the m arks made during disassem bly. from center (fig. 4), rem ove steering wheel as out­
Tighten the pitman shaft nut to specifications. lined under “ Steering Wheel - Removal’’; center high
point on gear, reposition and re in sta ll the wheel.
CAUTION: If a clamp type pitman arm is used,
spread the pitm an arm just enough, with a Steering Column Lower Bearing Adjustment
wedge, to slip the arm onto the pitm an shaft. Do
not spread the clamp m ore than required to slip 1. Loosen clamp on ste erin g shaft.
over pitm an shaft with hand p re s s u re . Do not 2. Applying 50 lb. force to the steering wheel end of the
ham m er the pitman arm onto the pitman shaft.
Be sure to install the hardened steel washer steering shaft, adjust clamp to obtain clearances
before installing the nut. indicated in Figure 5.
3. Tighten clamp bolt to specified torque.
10. Install the horn button cap and connect the battery
ground cable. Shifter Tube Adjustment

Steering Gear High Point Centering-C-P 10, C 20-30 3-Speed Transmission

1. Set front wheels in stra ig h t ahead position. This can 1. Loosen adjusting ring attaching screw s and clamp
be checked by driving vehicle a short distance on a bolt.
flat surface to determ ine steering wheel position at
which vehicle follows a straight path.

2. With front wheels se t stra ig h t ahead, check position
of m ark on w orm shaft designating ste e rin g gear high
point. This m ark should be at the top side of the
shaft at 12 o'clock position and lined up with the
m ark in the coupling lower clamp.

3. If g ear has been moved off high point when setting
wheels in straight ahead position, loosen adjusting
sleeve clamps on both left and right hand tie rods,
then tu rn both sleeves an equal num ber of turns in
the sam e direction to bring gear back on high point.

NOTE: Turning the sleeves an unequal number
of tu rn s o r in different directions will d isturb
the to e-in setting of the wheels.

4. Readjust to e-in as outlined in Section 3 (if n ecessary).

Steering Wheel Alignment

NOTE: On C -P 1 0 -20-30 s e rie s units check
steering gear for high point centering before
checking steering wheel alignment.

10-30 CHEVROLET TRUCK SERVICE MANUAI