Hummer H1 (2006+). Manual — part 252

8-24

Steering System

_____________________________________________________________

INPUT SHAFT PRELOAD ADJUSTMENT

1.

Remove the input shaft adjustment screw cap and loosen the locknut to allow free movement of the screw.

2.

With an inch pound torque wrench, tighten the adjustment screw to 100 lb-in. (11 N•m) to preload the bearing.

3.

Back off the adjustment screw then retorque the adjustment screw to 30 lb-in. (3 N•m)

4.

While holding the adjustment screw in position to prevent movement, tighten the lock nut to 25 lb-ft. (34 N•m).

5.

Install the adjustment screw cap and torque to 20 lb-ft. (41 N•m).

INSTALLATION AND SYSTEM BLEEDING

1.

Install the steering gear into the vehicle (Refer to section 8).

NOTE: Should The Front Geared Hubs Contact The Stops Under Pressure, Release The Wheel Immediately! Damage To The
Steering System May Result From Operating Against The Stops Under Pressure.

2.

Refill the steering system and start the engine, gently cycle the steering from side to side without hitting the stops to assist in
removing the air from the system. The brake pedal should also be depressed several times to purge any trapped air from the
brake hydroboost assembly.

3.

After several cycles of the steering and brake system, stop the engine and refill the reservoir as required.

4.

Check the adjustment of the vehicle steering stops on the front geared hubs (Refer to section 6).

5.

With the vehicle on a smooth level surface, start the vehicle and while in Park, turn the wheel full to the left then right and note
the clearance to the steering stops. The steering gear should stop wheel travel with 1/8 inch clearance to the stop. Should the
geared hub stop hit the control arm or the clearance be greater than 1/8 inch, the limit plunger requires adjustment.

LIMIT PLUNGER ADJUSTMENT

1.

Locate the limit plungers on each end of the steering gear, remove any dust caps to access the plunger ends.

2.

Position the steering wheel straight ahead and release the steering wheel.

3.

Using a small straight bladed screwdriver, turn the limit plunger in to reduce travel or out to bring the hub closer to the stop.
Do not turn the plunger with pressure on the system as damage to the seals may result.

4.

After adjusting the plunger turn the wheel full left and right again. Note the clearance to the steering stops and adjust the
plungers accordingly to obtain the correct 1/8 inch clearance.

5.

After proper clearance is obtained, install any dust caps removed to adjust the plungers.

10-1-08

____________________________________________________________

Steering System 8-25

5745804

INTERMEDIATE STEERING SHAFT REPLACEMENT

NOTE: Ensure the front wheels are in the straight-ahead position while removing and installing the intermediate steering shaft.

Removal

1.

Remove the close-out panel.

2.

Remove the three nuts, six washers, and the three screws from the dust boot (Figure 8-24).

3.

Remove the bolt on the intermediate steering shaft yoke at the steering gear.

NOTE: Before performing step 4, put scribe marks showing the position of the yoke relative to the splines.

4.

Remove the bolt on the intermediate steering shaft yoke at the steering column and remove the shaft.

Figure 8-24: Intermediate Steering Shaft Removal

Installation

1.

Align the hole in the yoke with the notch on the steering gear splines. Insert the bolt through the yoke and tighten the locknut
to 60 lb-ft (81 N•m) (Figure 8-24).

2.

Align the scribe marks and slide the yoke onto the steering column splines. Insert the bolt through the yoke and tighten the
locknut to 60 lb-ft (81 N•m).

3.

Apply silicone spray or equivalent to the end of the steering shaft. Secure the dust boot with three screws, six washers and the
three nuts.

4.

Lubricate the steering shaft at the universal joints.

5.

Install the close-out panel.

INTERMEDIATE STEERING SHAFT DUST BOOT REPLACEMENT

Removal

1.

Remove the close-out panel.

2.

Remove the three nuts, six washers, and the three screws from the dust boot (Figure 8-25).

STEERING COLUMN

DUST BOOT

INTERMEDIATE

STEERING SHAFT

STEERING GEAR

11-1-05

8-26

Steering System

_____________________________________________________________

NOTE: Before performing step 3, put scribe marks showing the position of the yoke relative to the splines.

3.

Remove the bolt on the yoke and pull the intermediate steering shaft from the steering column.

4.

Remove the four locknuts, eight washers, four screws, spacer, and the dust boot from the cowl panel and the intermediate
steering shaft.

Installation

1.

Secure the spacer and the dust boot to the cowl panel with the four screws, eight washers and the four locknuts. Tighten the
locknuts to 60 lb-ft (81 N•m) (Figure 8-25).

2.

Insert the intermediate steering shaft through the dust boot. Align the scribe marks and slide the yoke onto the steering column
splines. Tighten the locknut on the yoke to 60 lb-ft (81 N•m).

3.

Apply silicone spray or equivalent to the end of the steering shaft. Install the three screws, six washers, and the three nuts on
the dust boot.

4.

Install the close-out panel.

Figure 8-25: Intermediate Steering Shaft Dust Boot Replacement

POWER STEERING PUMP AND PULLEY REPLACEMENT

Removal

1.

Disconnect the return lines and the high pressure line from the back of the pump (Figure 8-26).

2.

Remove the serpentine belt from the power steering pump pulley.

3.

Remove the three bolts holding the mounting bracket to the block.

4.

Remove the pump assembly.

5.

Using puller J–25034-C or equivalent, remove the pulley from the pump.

6.

Remove the three bolts going through the mounting bracket into the front of the pump.

Installation

1.

Install the three bolts going through the mounting bracket into the front of the pump.

CAUTION: In next step, do not attempt to drive the pulley onto the pump shaft with a hammer. The pulley and pump ring will be dam-
aged.

STEERING COLUMN

COWL

DUST

SPACER

INTERMEDIATE

STEERING SHAFT

BOOT

PANEL

11-1-05

____________________________________________________________

Steering System 8-27

5745804

2.

Press the pulley onto the pump using pulley installer J–25033-C or equivalent. The pulley should be flush +/- 0.25 mm (0.010
inch) with the end of the power steering pump shaft.

3.

Apply a non-hardening thread sealant to the studs on the back of the pump and secure the support bracket with the two nuts.
Tighten the nuts to 45 lb-ft (61 N•m).

4.

Maneuver the pump into position behind the power steering bracket.

5.

Secure the pump to the mounting bracket with the three bolts.

6.

Secure the support bracket to the block with the bolt.

7.

Connect the two return lines to the power steering pump.

8.

Check the condition of the O-ring seal and connect the high pressure line to the back of pump.

9.

Purge the air from the power steering system.

10. Start the engine and check for leaks.

Figure 8-26: Power Steering Pump and Pulley

POWER STEERING HYDRAULIC SYSTEM PRESSURE AND RETURN HOSE REPLACEMENT

NOTE: Removal and installation procedures are basically the same for all hydraulic system pressure and return hoses. This proce-
dure covers the power steering pump to hydro-boost return hose and the steering gear to hydro-boost pressure hose.

Removal

1.

Disconnect the return hose from the power steering pump and the hydro-boost.

2.

Remove the locknut, washer, bolt and the two clamps from the control valve hose and the return hose.

3.

Remove the locknut, two washers and the bolt securing the two clamps and the harness clamp to the power steering line bracket.

4.

Disconnect the pressure hose from the hydro-boost and the steering gear and remove the pressure hose. Remove the O-ring
seal from the pressure hose. Check the condition of the O-ring seal and replace if necessary (Figure 8-27).

Installation

1.

Connect the pressure hose to the steering gear and the hydro-boost (Figure 8-28).

2.

Connect the return hose to the power steering pump and the hydro-boost with the two clamps.

PULLEY

POWER STEERING

SUPPORT BRACKET

POWER

STEERING

PUMP

PRESSURE

HOSE

RETURN

HOSE

RESERVOIR

SUPPLY

HOSE

MOUNTING

BRACKET

11-1-05