CKFCar Known Faults
CriticalAffected: 2004-201060,000–110,000 miles

Vauxhall Astra Astra H 1.7 CDTi 100bhp — M32 Gearbox Bearing Failure

If fitted with the 6-speed M32 gearbox, the Astra H suffers from catastrophic end-case bearing failure. A whining noise in 5th and 6th gear is the hallmark sign.

Severity

Critical

DIY Difficulty

Professional Only

Est. Cost

£400–£1200

OBD Codes

None

Component Diagram

Wheel Bearing

Typical layout and location for the Wheel Bearing assembly.

Wheel Bearing diagram
Reference Illustration

Symptoms

  • Whining noise in 1st, 2nd, 5th, and 6th gears
  • Gear stick moves violently when lifting off the throttle in 1st gear
  • Crunching when selecting gears

Root Cause

Poor internal lubrication design and inadequate pre-load on the bearings from the factory causes the mainshaft bearings to overheat and pit.

How To Fix

  1. If caught early (whining just starting): gearbox can be repaired in-situ by replacing the end-case bearings (£400-600)
  2. If left until crunching starts: the casing is likely destroyed, requiring a fully reconditioned gearbox (£800-1,200)
  3. Overfill the new gearbox with 2.2-2.4 litres of high-quality oil (Fuchs Titan Sintofluid) rather than the factory 1.9L.

Estimated Repair Costs

Repair OptionEst. Cost (GBP)
DIY (parts only)£160–£480
Independent Garage£400–£1200
Main Dealership£640–£1920

Other Faults on This Variant

EGR Valve Failure

Moderate
2004-201050,000–100,000 miles£80–£350

The Isuzu-sourced Z17DTH and Z17DTJ engines in the Astra H have a well-documented EGR valve failure. Carbon deposits cause the valve to stick, resulting in power loss and increased emissions.

DPF Blockage

Moderate
2007-201040,000–90,000 miles£200–£800

DPF-equipped Astra H 1.7 CDTi models (post-2007) suffer from the same DPF blockage issues as most diesel Vauxhalls of this era. Urban use is the root cause.

Dual Mass Flywheel Failure

Moderate
2004-201080,000–150,000 miles£650–£1000

DMF wear on the Astra H 1.7 CDTi is a high-mileage inevitability. The flywheel's internal dampers lose effectiveness, causing vibration and judder that makes the car unpleasant to drive.

Disclaimer: Repair cost estimates are indicative and based on community data. Always get a quote from a qualified mechanic before proceeding with any repair.