Recalls: Opel Mk.4 Corsa OPC
Overview
Manufacturers, or importers, issue recalls for defects or faults which have the potential to cause injury. Generally, manufacturers will inform the original buyers if their vehicle is subject to a recall and of the steps required to remedy the defect or fault. Please note that the recalls below (if any) are for Australian-delivered vehicles only. Furthermore, the number of recalls should not be taken as an indication of a model’s reliability or its safety more generally.
Recalls: Opel Mk.4 Corsa OPC
Opel Corsa OPC: omissions from owners manual
In July 2014, a recall was issued for Spanish and German-built Opel Corsa vehicles. In these vehicles, the owners manual did not contain some specific information required for Australia, such as child restraint loading precautions. To rectify this problem, Holden was to send owners an updated manual (via registered post). The Spanish-built Corsa vehicles that were recalled were manufactured from 15 December 2011 to April 2013 and had VINs in the range W0L0SDL68C4074621 to W0L0SDL08D4191279. The German-built Corsa vehicles that were recalled were manufactured from 6 December 2011 to 12 June 2013 and had VINs in the range W0L0SDL08C6036877 to W0L0SDL08D6077790 (PRA 2014/14209).
Problems and faults: Opel Mk.4 Corsa OPC
Overview
This section identifies potential problems, causes and fixes based on the experiences of owners and repairers, online sources and technical service bulletins. This information is provided solely for reference purposes and AustralianCar.Reviews recommends that only properly qualified persons carry out repairs or modifications. Furthermore, the number of items below should not be taken as an indicator of a model’s reliability or the frequency with which they may occur.
To report a problem or fault to the AustralianCar.Reviews team, please use the Contact Us form. Note that AustralianCar.Reviews does not offer advice on automotive problems or disputes; such enquiries will not receive a reply. For vehicles purchased from dealers after 1 January 2011, please see our Australian Consumer Law fact sheet.
Opel Astra GTC 1.4 Turbo and 1.6 Turbo: M32 transmission bearing failure
Symptoms of worn bearing
For Opel Astra GTC vehicles with 1.4- and 1.6-litre turbocharged petrol engines, the bearing on top of the sixth gear in the M32 manual transmission is susceptible to wear and, eventually, failure. Symptoms of a worn bearing include –
- Gearstick movement: when disengaging the clutch in 1st gear and pulling away – while holding the gearstick – the gearstick may move back into your hand by around 10 to 20 mm (the greater the movement, the worse the bearing wear). After further wear, this movement may also occur when the transmission is in fifth or sixth gear;
- A whining noise in 1st, 2nd, 5th and 6th gear: a whining noise may be heard from the glovebox area when driving in 1st, 2nd, 5th and 6th gears. In particular, a whining noise may be heard when driving at highway speeds in sixth gear and the accelerator is pressed; and,
- A whining noise in all gears: a whining noise – which is proportional to vehicle speed – may be heard in all gears regardless of whether the clutch is engaged or disengaged.
Explanation of symptoms
The bearing which is susceptible to wear sits on top of the output shaft that is responsible for gears 1, 2, 5 and 6 – this is why these gears exhibit the symptoms described above. For these symptoms,
- It is wear of the bearing rollers which causes them to be loose and have excessive play (see video below; the HSV VXR also had the M32 transmission). This, in turn, causes movement in the gearstick since the gear linkage is connected to an internal selector, and bearing wear causes the shaft inside the gearbox to move up and down when power is applied. The shaft then moves the selector ring which feeds back to the gearstick; and,
- Whining noises are caused by pitted pinion bearings which may be due to metal fatigue. It is understood that M32 transmissions produced from 2010 to 2012 are more susceptible to pitted pinion bearings since General Motors replaced the Timken and SNK bearings with FAG and NGBC bearings.
Cause of bearing wear
The primary cause of bearing wear is inadequate lubrication and subsequent overheating – this may be attributed to:
- The design of the M32 transmission: while the original M32 transmission was introduced in 2004, a revised ‘Generation 2’ M32 transmission was introduced for the 2012.5 ‘model year’ (though some vehicles were not fitted with the revised transmission until 2013). The ‘Generation 2’ M32 transmission had:
- Revised end casings in which there was an oil feed to the output shaft end bearing that passed through the input shaft end bearing; and,
- Larger bearings (62 mm compared to 55 mm) with greater surface area.
- Oil overheating: if the gearbox oil overheats, it will no longer conform to its specifications and adequately lubricate the bearings; and,
- Inadequate servicing: oil deteriorates over time and needs to be replaced according to the scheduled service intervals.
Management and ‘clutch slip’ warning
When the driver becomes aware of the symptoms above, it is recommended that 5th and 6th gears are avoided and the 3rd and 4th gears are used instead since this transfers the engine’s torque to the other output shaft and takes the load off the worn bearing.
If the worn bearing is not replaced, the outer bearing race can start to spin and wear the casing. Eventually, this can punch a hole in the casing, the bearing may collapse, the rollers can release and cause damage to the gears – if this occurs, the entire transmission has to be replaced. Owners have described clutch slip as a warning that the bearing is about to collapse.
Repair options
In repairing the M32 transmission, the standard replacement option is to replace all six bearings – this includes the faulty ‘6th gear’ bearing, the 4th gear output shaft bearing, both input shafts and both pinion bearings. This requires removal of both input and output shafts/gears sets, and replacing the inner and outer races. Since this method does not address the lubrication deficiencies of the original M32 transmission, however, it is recommended that the ‘Generation 2’ casing with larger bearings be fitted. To install the ‘Generation 2’ casing, the entire gearbox has to be removed.
For further information about the M32 transmission, please see:
- Eco Torque UK: M32 Gearbox – uprated bearings and end casing;
- Tech 2 Guru: Vauxhall M32 six-speed manual transmission; and,
- WG Motor Works: M32 Gearbox.
