Steering - Knocking Noise at Low Speeds
File in Section: 3 - Steering/SuspensionBulletin No.: 53-32-02A
Date: August, 1996
Subject:
Knocking Noise Heard at Low Speeds Over Rough Roads
(Replace Rack Bearing or Install Restrictor)
Models:
1995-96 Chevrolet Cavalier
1995-96 Pontiac Sunfire
This bulletin is being revised to add the 1996 model ear and revise the "Correction" procedure which now includes service parts. Please discard Corporate Bulletin Number 53-32-O2 (Section 3 - Steering/Suspension).
Condition
Some owners may comment on a loud knocking noise coming from the front of the vehicle when driving between 9 and 12 mph over rough roads. There are two separate causes and corrections for this general condition.
Cause
The vibrations from the suspension damping the rough roads are being transmitted to the steering gear and through the power steering system.
Correction
Correction 1
A knocking noise heard while driving straight ahead involves 1995-96 vehicles built prior to the above VIN breakpoints. This condition may be corrected by replacing the steering gear rack bearing and spring with a service kit, P/N 26063086.
Use the following repair procedure:
See Figure 1. (Numbers in parenthesis below refer to callouts in figure).
1. Remove steering gear (5). Refer to Section 3B in the Service Manual).
2. Secure steering gear on workbench.
3. While holding the adjuster lock plug (3) stationary, loosen the adjuster plug locknut (4) and remove.
4. Remove adjuster plug (3).
5. Remove spring (2).
6. Remove bearing (1).
7. Install bearing (1).
8. Install spring (2).
9. Install adjuster plug (3).
10. Tighten the adjuster plug (3) to 15 N.m (11 lb ft) (turn clockwise). Then back-off (turn counterclockwise) 45°. Refer to Figure 1.
11. While holding the adjuster plug (3) stationary, reinstall and tighten the adjuster plug locknut (4). Tighten to 60-90 Nm (44-66 lb ft).
12. Recheck the steering gear turning torque not to exceed 2 Nm (18 lb in). Make sure there is no lumpiness or binding when turning steering shaft.
13. If lumpiness, binding, or turning torque exceeds 2 Nm (18 lb in), repeat Step 3 and set the back-off at 50°, then go to Step 5.
14. Reinstall the steering gear (refer to Section 3B of the Service Manual).
15. Test vehicle for steering wheel returnability. If returnability is unacceptable, repeat Steps 1-7.
Correction 2
A knocking noise heard while turning and driving over a bump at the same time involves 1996 vehicles with 2.2L engines (VIN 4 - RPO LN2) built prior to the above listed VIN breakpoints. This condition may be corrected by installing a power steering restrictor valve, P/N 22592200, into the pump reservoir inlet. Restrictor can only be installed on vehicles equipped with power steering cooler pipes.
Use the following installation procedure:
1. Inspect vehicle to insure vehicle is equipped with a power steering cooler pipe.
2. Install restrictor in the inlet tube of the power steering fluid reservoir.
3. Restrictor should be pushed in by hand until snug, not forced or hammered.
4. Return hose should be pushed over the restrictor and inlet tube, then clamped.
Parts Information
Parts are currently available from GMSPO.
Warranty Information
For vehicles repaired under warranty, use the table.