Parts for your 2004 Holden Commodore-Bump stops

2004 Holden Commodore bump-stops

Bump-stops are fitted to the 2004 Holden Commodore. This is supported by factory literature (Holden Commodore VY/VZ Service Manual – Front and Rear Suspension sections), the GM Holden Electronic Parts Catalogue listing “jounce bumper/bump stop” components for front struts and rear suspension across sedan, wagon and ute variants, and major aftermarket catalogues from Monroe and KYB that supply front strut boot-and-bump-stop kits for VY/VZ models. So, they’re very much relevant to this vehicle.

On a 2004 Commodore, the bump-stops are the quiet heroes of the suspension. They act as progressive cushions that limit how far the suspension can travel on big hits, sharp driveway entries, potholes or when the car’s loaded up for a trip. Up front, the jounce bumper typically sits on the strut shaft inside or beneath the dust boot. At the rear, there’s a chassis-mounted bump stop that contacts the axle or control arm, whether the car runs the live-axle layout (common on some utes and base models) or the independent rear setup found on higher-spec variants.

Their job is to protect shocks/struts, springs and body mounts from smashing together at full compression, reduce harsh thuds, and keep tyre contact more predictable when the road turns ugly. Because they’re made from microcellular polyurethane or rubber, they can perish with age, heat, oil contamination or constant heavy loading and towing.

Good servicing practice is to inspect the bump-stops whenever the Commodore is on a hoist for brakes, shocks, springs or wheel alignment work. Many techs replace them as a set when fitting new struts or shocks, because they’re relatively inexpensive insurance and often require similar labour to access. Front strut bump-stops usually mean removing the strut assembly and using a spring compressor. Rear stops are often simpler but still need proper support stands and torquing of any suspension bushes at normal ride height.

• Signs they need attention: visible cracks or missing chunks, the stop has gone soft or turned powdery, the dust boot is torn, or there’s a harsh bang on big bumps.
• When to replace: at shock/strut change, if damaged or oil-soaked, or if the car regularly tows or carries heavy loads.
• Tips: fit quality OE-spec components, ensure the boot fully covers the strut shaft, and replace in pairs across an axle.

Look after the bump-stops and the Commodore rides better, the dampers last longer, and the suspension doesn’t cop a hiding on rough Kiwi or Aussie roads.

Does a 2004 Commodore have front and rear bump-stops?

Yes. The front struts use a jounce bumper (bump-stop) in or under the dust boot, and the rear has body-mounted bump-stops that contact the axle or control arm. This applies across sedan, wagon and ute variants, with either live axle or independent rear suspension.

How often should bump-stops be replaced?

There’s no strict kilometre interval. Inspect them at regular services and whenever shocks or struts are replaced. Swap them if they’re cracked, missing, oil-soaked or the boot is torn. Many owners replace fronts and rears during damper changes to avoid double labour and keep the ride consistent.

Can worn bump-stops cause a WOF or RWC issue?

They can. In both NZ (WOF) and Australia (RWC), missing or badly deteriorated bump-stops may be flagged because they’re part of the suspension’s safety and travel control. If a tech notes damage or absence, expect a recommendation to replace them before sign-off.