Parts for your 2020 Holden Commodore-Centre bearing

2020 Holden Commodore centre-bearing — what’s fitted and when it matters

Based on the factory driveline layout, a centre-bearing is only relevant on 2020 Holden Commodore (ZB) models with AWD. Technical references that show this include: GM Service Information (SI) for ZB Commodore/Opel Insignia B (sections covering Propeller Shaft – AWD), which depict a two-piece prop shaft with a centre support bearing, the Holden Electronic Parts Catalogue (EPC), Group 04 – Propeller Shaft, which lists a “propeller shaft centre support bearing” for AWD VINs but not for FWD VINs, and the Opel Insignia B workshop material plus GKN’s Twinster AWD system description, which detail a front PTU, two-piece propshaft and rear drive module. FWD Commodores don’t use a centre-bearing because there’s no long propeller shaft—the transaxle drives the front wheels directly, so a centre support isn’t needed.

Where fitted (AWD V6 variants like RS-V, VXR and certain Tourer models), the centre-bearing sits mid-way along the two-piece propeller shaft. Its job is to support the shaft, control its alignment and curb vibration as torque is sent from the front power transfer unit to the rear drive module. The bearing’s rubber isolator absorbs movement and helps keep the driveline smooth under load, on coarse chip roads, and during quick take-offs.

It’s not a routine replacement item, but it’s smart to have it checked whenever there’s driveline NVH. Classic tells include a droning or humming that changes with road speed, a shudder on take-off, or a thump on gear changes. If the car is safely raised, cracking or separation in the rubber support, excessive play in the bearing, or witness marks around the bracket are red flags.

According to GM SI and the Holden EPC, the propeller shaft on these models is serviced as a balanced assembly, and the centre support bearing isn’t normally sold separately. That means the recommended repair for a failed centre-bearing is to replace the complete shaft to maintain balance and avoid repeat NVH. Some aftermarket suppliers may offer a stand-alone bearing, but mixing parts can introduce imbalance and shorten joint life. A workshop familiar with ZB AWD is the best bet if chasing a quiet, factory-correct result.

• When replacing: follow OEM alignment marks, renew any one-time-use bolts, and torque fasteners to spec.
• Inspect related items at the same time: CVs at each end of the prop shaft, heat shields, mounts, and rear drive module bushes.
• After install: road-test across 60–110 km/h to confirm no residual vibration, and check for contact or exhaust rattles.

For FWD 2020 Commodore variants, a centre-bearing isn’t used because there’s no rear driveline to support. Some FWDs do have an intermediate shaft with a support bearing on one side, but that part isn’t the same as a prop-shaft centre-bearing and isn’t catalogued as such for ZB FWD models.

FAQs

Does my 2020 Commodore have a centre-bearing?
Only the AWD variants do. If it’s an AWD V6 (e.g., RS-V, VXR, some Tourers), it has a two-piece prop shaft with a centre support bearing. FWD four-cylinder models don’t have one because there’s no rear driveline. A quick underbody glance for a prop shaft running down the tunnel is the easiest check.

What symptoms point to a worn centre-bearing on a ZB AWD?
Look for a road-speed-related hum, a shudder on take-off, or a clunk when shifting between drive and reverse. Visible cracks in the rubber isolator or excess play at the bearing mount are strong signs it’s time to repair.

Can the centre-bearing be replaced on its own?
Factory documentation (GM SI/EPC) treats the prop shaft as a balanced assembly, so the recommended fix is to replace the complete shaft. While some aftermarket options may sell the bearing only, that route risks imbalance and persistent vibration.