Lower steering shaft needs replacement.

Steering Column Replacement Hope this helps?

Tools Required

• J 42640 Steering Column Lock Pin
• J 41352 Modular Column Holding Fixture

Removal Procedure

Warning! Refer to SIR Caution in Cautions and Notices.
Caution! The wheels of the vehicle must be straight ahead and the steering column in the LOCK position before disconnecting the steering column or intermediate shaft from the steering gear. Failure to do so will cause the SIR coil assembly to become uncentered, which may cause damage to the coil assembly.
Caution! Once the steering column is removed from the car, the column is extremely susceptible to damage. Dropping the column on its end could collapse the steering shaft or loosen the plastic injections which maintain column rigidity. Leaning on the column could cause the jacket to bend or deform. Any of the above damage could impair the column's collapsible design. If it is necessary to remove the steering wheel, use only the specified steering wheel puller. Under no conditions should the end of the shaft be hammered upon as hammering could loosen plastic injections which maintain column rigidity.

1. Disable the SIR system. Refer to SIR Disabling and Enabling Zone 3 in SIR.




2. Insert J 42640 into the steering column access hole in order to lock the steering column. This will maintain the correct orientation.
3. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.




4. Remove the intermediate shaft lower pinch bolt.
5. Remove the intermediate shaft from the steering gear.
6. Lower the vehicle.




7. Remove the knee bolster. Refer to Bracket Replacement - Knee Bolster in Instrument Panel, Gages and Console.
8. Disconnect the steering column wiring harness connector from the main body wiring harness.
9. Disconnect the shift lever cable from the linear shift assembly.




10. Remove the shift cable retaining clip.




11. Press the shift cable tabs (1) together and remove the shift cable (2) from the steering column.



Caution! The steering column should never be supported only by the lower support bracket. Damage to the lower support could result.
Important Stabilize the studs in order to remove the nuts securing the steering column to the instrument panel.

12. Support the column.




13. Remove the lower steering column retaining nuts.
14. Remove the upper steering column retaining nuts.
Important Discard the clips at the upper steering column support, if equipped. These clips are for assembly plant usage only.

15. Remove the steering column from the vehicle.
16. Install the steering column into J 41352 .

remove lower ball joint and remove axle nut in the center of spindle. then move the spindle out of the way separating the axle from the spindle.

you need first disconnect negative battery cable. you need steering wheel puller you have to remove steering.look under hood disconnect flange end of the steering shaft at the flexible coupling separate the coupling from the lower end of the steering column. you have to go inside vechicle remove lower steering column cover yoo have to remove steering column dash to panel screws then you have to remove shift linkages and remove disconnect electrical wiring connector to turn signal and ignition switch.your model truck shouldnt have the floor board mounting screw hold column to the floor.

I alway's replace both upper and lower shafts. They both have noise issue's from lack of lube when made. Pete

here hope this helps for a 98 model but very similair

1998 GMC Truck Jimmy - 4WD ' Blazer, Bravada, Jimmy, S10 Pickup, Sonoma VIN S/T Service Manual ' Steering ' Power Steering System ' Repair Instructions ' Document ID: 416283
Steering Gear Replacement (4WD) Removal Procedure Tools RequiredJ 24319-B Steering Linkage Puller
Notice: Do not rotate steering shaft after steering column has been removed. Damage to SIR components may occur.

1. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement in Engine Controls 4.3L.




2. Place a drain pan below the steering gear.
3. Remove the inlet and the outlet hoses from the power steering gear.
Cap or tape the ends of the hoses and the gear fittings in order to prevent dirt from entering the system.




4. Remove the intermediate shaft shield from the steering gear.




5. Remove the lower intermediate shaft coupling bolt.
6. Draw alignment marks on the lower intermediate shaft coupling and the steering shaft.
7. Remove the lower intermediate shaft coupling from the steering shaft.
8. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
9. Remove the steering linkage shield. Refer to Steering Linkage Shield Replacement in Steering Linkage.




10. Remove differential carrier shield mounting bolts.
11. Remove the differential carrier shield.




12. Remove the pitman arm ball stud nut at the relay rod.




13. Disconnect pitman arm from relay rod using J 24319-B .




14. Remove the steering gear mounting bolts and the washers from the frame.
15. Remove the steering gear.
16. Remove the pitman arm. Refer to Pitman Arm Replacement in Steering Linkage.

I found for myself that disconnecting the steering knuckle from the strut ,removing the tie rod and the lower ball joint also from the steering knuckle and remove it so that its out of the way.This makes it allot easier to remove the half shaft.Also be sure to hang the caliper with wire so you don't damage your break hoses.Most half shafts are 65 to 85 ft lbs but the exact torque can be gotten from your local auto parts store.

To Remove:

1. Before servicing the vehicle, refer to the precautions at the beginning of this section. NOTE: The wheels of the vehicle must be straight ahead and the steering column in the LOCK position before disconnecting the steering column or intermediate shaft from the steering gear. Failure to do so will cause the SIR coil assembly (clock spring) to become uncentered, which may cause damage to the assembly.
   
2. Lock the steering column by installing the J42640 into the underside of the steering column.
3. Raise and support the vehicle.
4. Remove the tires and wheels.
5. Remove the power steering gear heat shield.
6. Remove or disconnect the following: CAUTION
   Failure to disconnect the intermediate shaft from the rack and pinion stub shaft can result in damage to the steering gear and/or intermediate shaft. This damage can cause loss of steering control, which could result in personal injury.
   
• Intermediate shaft lower pinch bolt and coupling from gear
• Pressure and return pipes from the gear
• Electrical connector, if equipped
  Stabilizer shaft links at lower control arms
• Remove the left stabilizer shaft insulator.
• Rotate the stabilizer shaft to access steering gear bolts.
• The outer tie rod retaining nuts.
• Using J24319-B separate the outer tie rods from the steering knuckles.
• Rack and pinion attaching bolts
• Rack and pinion assembly through the left wheel opening.
7. Transfer the outer tie rods if replacing the power steering gear.

To Install:

1. Install or connect the following:
   • Rack and pinion assembly through the left wheel opening and tighten the bolts to 70 ft. lbs. (95 Nm)
   • Electrical connector, if equipped
     Pressure and return lines to the steering gear and tighten the fittings to 22 ft. lbs. (30 Nm)
   • Heat shield and bolts. Tighten the bolts to 7 ft. Lbs. (10 N)
   • Install the left stabilizer shaft insulator.
2. Install stabilizer shaft Links to lower control arms
3. Intermediate shaft to the steering gear and tighten the pinch bolt to 35 ft. lbs. (47 Nm)
4. Install the outer tie rods to the steering knuckles.
5. Install the outer tie rods retaining nuts. torque the nuts to 22ft.lbs(30 Nm) plus an additional 180 degrees.
6. Install the tires and wheels.
7. Lower the vehicle.
8. Remove the steering column anti rotation pin from the steering column.
9. Fill and bleed the power steering system.
10. Adjust the front toe.

Lock the steering column by installing the Steering Column Anti Rotation Pin tool J 42640 into the underside of the steering column--Aurora


Steering gear mounting bolts--Aurora




Power Rack & Pinion Steering Gear Heat Shield Removal & Installation To Remove:

1. Raise and support the vehicle.
2. Remove or disconnect the following:
   • The stabilizer shaft links.
   • Rotate the stabilizer shaft downward.
   • The electrical harness clip.
   • Power steering gear heat shield mounting bolts.
   • The heat shield.

To Install:

1. Install the power steering gear heat shield.
2. Install or connect the following:
   • The mounting bolts And torque to 89in.lbs.(10 Nm)
   • The electrical harness clip.
   • Rotate the stabilizer shaft into position.
   • The stabilizer shaft links.
3. Lower the vehicle.

Figure of heat shield removed from above rack bolts with location shown

Power Steering Gear Replacement
Removal Procedure

1. Raise the vehicle on a hoist.
2. Remove the tires and wheels.
3. Remove the stabilizer shaft links from the control arms.
4. Remove the tie rod ends from the steering knuckle.

5. Remove the intermediate shaft lower pinch bolt from the power steering gear.

1. Remove the stabilizer shaft.

7. Remove the power steering hoses from the from the power steering gear.

8. Remove the power steering gear bolts from the frame.

1. Remove the power steering gear through the left wheel opening.

Removal Procedure

Notice: Do not rotate steering shaft after steering column has been removed. Damage to SIR components may occur.

Lock the steering column through the access hole in the steering column lower trim cover using the J 42640.
Remove the air cleaner assembly. Refer to Air Cleaner Outlet Resonator Replacement in Powertrain Management.Remove the intermediate shaft shield from the steering gear.Place a drain pan below the steering gear. Remove the pressure and the return hoses from the power steering gear. Cap or tape the ends of the hoses and the gear fittings in order to prevent dirt from entering the system.Remove the lower intermediate shaft coupling bolt. Draw alignment marks on the lower intermediate shaft coupling and the steering shaft. Remove the lower intermediate shaft coupling from the steering shaft. Remove the pitman arm. Refer to Pitman Arm Replacement.Remove the steering gear mounting bolts and the washers from the frame. Remove the steering gear.
Installation Procedure


Install the steering gear. Notice: Refer to Fastener Notice in Service Precautions. Install the power steering gear to the frame washers and the mounting bolts. Tighten Tighten the power steering gear to frame mounting bolts to 75 Nm (55 ft. lbs.). Install the pitman arm. Refer to Pitman Arm Replacement.Install the lower intermediate shaft to the power steering gear. Ensure that the alignment marks line up. Install the lower intermediate shaft coupling bolt. Tighten Tighten the lower intermediate shaft coupling bolt to 35 Nm (26 ft. lbs.). Install the pressure and the return hoses to the power steering gear. TightenTighten the pressure hose to 25 Nm (18 ft. lbs.) for the vehicle equipped with the 2.2L engines. Tighten the pressure hose to 30 Nm (22 ft. lbs.) for the vehicle equipped with the 4.3L engines. Tighten the return hose to 25 Nm (18 ft. lbs.). Install the intermediate shaft shield to the power steering gear. Install the air cleaner assembly. Refer to Air Cleaner Outlet Resonator Replacement in Powertrain Management. Unlock the steering column by removing the J 42640 from the steering column lower steering column trim cover access hole. Bleed the power steering system. Refer to Bleeding Power Steering System in Steering / Service and Repair.

this is for 1996, don't have 89.
these may be steps you need

1. Remove pinch bolt from steering shaft flex coupling.
   

1. Disconnect shift cable from selector lever pivot.
   

1. Remove shift cable from steering column lower mounting bracket by pushing tab on cable in and sliding cable off bracket.
   

1. Disconnect ignition switch (11572) by loosening bolt and removing connector. The bolt is part of connector and can not be removed.
   

1. While supporting steering column, remove four retaining nuts.
   

1. Disconnect collapsible intermediate shaft from U-joint at lower end of steering column.
   

1. Remove steering column from vehicle.