Thump Noise From Front Suspension: GM

GM Tech Tip: Clunk Or Thump Noise From Front Suspension

Some customers may comment on a clunk or thump noise coming from the front suspension while driving over rough road surfaces. This noise will typically occur when the front suspension is returning to the upward position after a hard downward stroke, such as after driving through a large rut or pothole.

Models:

2008-2011 Buick Enclave, LaCrosse, Lucerne

2011-2012 Buick Regal

2005-2010 Chevrolet Cobalt (Including SS)

2006-2011 Chevrolet HHR (Including SS)

2008-2009 Chevrolet Uplander

2008-2011 Chevrolet Aveo

2008-2012 Chevrolet Equinox, Impala, Malibu

2009-2012 Chevrolet Traverse

2010-2012 Chevrolet Camaro

2011-2012 Chevrolet Cruze, Volt

2008-2012 GMC Acadia

2010-2012 GMC Terrain

2007-2010 Pontiac G5

2008 Pontiac Grand Prix

2008-2009 Pontiac Montana SV6, Torrent

2008-2010 Pontiac G3, G6, Vibe, Wave

Condition

Some customers may comment on a clunk or thump noise coming from the front suspension while driving over rough road surfaces. This noise will typically occur when the front suspension is returning to the upward position after a hard downward stroke, such as after driving through a large rut or pothole.

Cause

This condition may be caused by the jounce bumper slamming into the upper spring seat because it is not retained in the correct up position. The jounce bumper loses position due to oil being deposited onto its retention fingers. The oil is from the strut leaking.

gm 1Correction

Inspect the front strut(s) for evidence of oil. The leak may be slight but will still cause a problem. If oil is present, replace the affected strut, jounce bumper and dust boot (shield). Before reassembling the strut assembly, glue the new jounce bumper and new dust boot (shield) to the upper spring seat using the steps listed below. To confirm this concern, the shield/bumper will easily slide up and down the strut shaft.

gm 21. Clean the surface area of the upper spring seat using fine sandpaper.

2. Apply a light coat of automotive adhesion promoter to the top of the dust boot (shield) on the inside edge and to the top of the bumper. Allow to dry 10 minutes.

3. Glue the bumper to the inside of the dust boot (shield) as shown. Use fast curing adhesive. Allow to cure thoroughly 5-10 minutes at room temperature.

gm 34. Apply a light coat of automotive adhesion promoter to the top of the dust boot (shield) and to the upper spring seat surface. Allow to dry 10 minutes.

5. Glue the dust boot (shield) to the upper spring seat as shown using the above recommended adhesive. Allow to cure thoroughly.

Courtesy of ALLDATA

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