HHR L4-2.4L (2010)
Stabilizer Link: Customer Interest
Suspension - Front Suspension Noise Concerns
TECHNICAL
Bulletin No.: 04-03-08-006E
Date: November 01, 2010
Subject: Steering and Front Suspension Noise Concerns - Clunk, Thump, Rattle, Knocking, Pop, Shudder, Vibration (Diagnosis and Perform Necessary
Repair)
Models:
2005-2010 Chevrolet Cobalt (Including SS)
2006-2010 Chevrolet HHR (Including SS)
2005-2006 Pontiac Pursuit (Canada Only)
2007-2010 Pontiac G5
2003-2007 Saturn ION
Supercede:
This bulletin is being revised to add 2010 model year and update Condition #7 with new part information. Please discard Corporate Bulletin Number
04-03-08-006D (Section 03 - Suspension).
This bulletin provides information on eight different steering/front suspension noise conditions.
Condition #1
Some customers may comment on a rattle or knocking noise that is heard in the front of the vehicle while driving at low speeds 8-24 km/h (5-15 mph).
This condition may be more noticeable while making a slow turn or on a loose/rough surface.
This condition can be duplicated by the technician using the following procedure:
1. On a rough or loose surface (i.e., gravel parking lot), make a sweeping turn (either direction) at 8-24 km/h (5-15 mph to load the steering column,
I-shaft and steering rack/gear mechanisms. The testing on a rough or loose surface will allow the wheels to oscillate slightly and will make the
rattle/knocking noise more evident and repeatable.
2. Release the steering wheel while making the turn to take load off of steering components. This should initiate the rattle/shudder noise, which is
generated by backlash in the steering assembly as it is in a no-load float condition.
3. Remove the 60 amp EPS fuse (1) in the underhood fuse block.
4. Test the vehicle as in Step 1. Since the EPS motor is no longer powered, only the I-shaft and steering gear/rack will be loaded as you make the
turn. If you hear the rattle/knocking noise during the turn, then the noise is being generated by the backlash within the steering column (assist
motor gear mechanism).
5. Replace the 60 amp EPS fuse and repeat Steps 1 and 2 to verify that the rattle/knocking noise disappears when turning (loading steering
mechanism) and can only be heard when releasing the steering wheel.
Correction #1
If the steering column is identified as the source of the rattle/knocking noise in the above test, replace the steering column.
Important
The noise in the steering column is generated from the metal to plastic gear backlash of the assist motor mechanism and will have a different
sound than that from the steering gear. If the customer comments that they still hear a noise, it may be a different sound from either the I-shaft
or the steering rack.
