MK5 Golf GTI

All Things Mk5 => Modifications & Technical Area => Technical Workshop => Topic started by: vRStu on June 09, 2010, 07:41:55 am

Title: DSG Gearbox Failure
Post by: vRStu on June 09, 2010, 07:41:55 am
I just read this, sounds like a catastrophic gearbox failure to me much like Dom's little incident.  Sounds like it was quite a serious one too -

Quote
Scene: 50mph going north at M5/M4 interchange, I shift from normal to sport mode, gearbox locks with engine braking effect causing dramatic deceleration, no warning to cars behind, 6 car pile up, wife and kids not happy (to say the least on the first day of our holiday), 4 cars (not R36) written off (thankfully no injuries), initial diagnostic locates no fault but after 12 days in the garage, car is finally diagnosed with catastrophic failure requiring a new part to be "made" (i.e. not off the shelf) (wife's words - I have yet to discuss precise details with the technician - but it took VW themselves to locate the fault), lead time is another 2 weeks, VW arguing about a temporary replacement car.

Result: R36 will be going once repaired, to be replaced by a Discovery 4.

Reason: all confidence in car has gone. Imagine if we had been travelling at 80mph.
Title: Re: DSG Gearbox Failure
Post by: Poppa Dom on June 09, 2010, 09:05:29 am
Totally sympathise with the guy - I was fortunate that mine did not happen on a motorway as would have been the case with my normaly daily commute, bu doing 25 in a 30mph zone just after midnight. Sounds like diff went and ceased, causing exactly the same effect that I had in mine. Not sure about the new part to be made - be interesting to get a follow up and see exactly what caused this failure.
Title: Re: DSG Gearbox Failure
Post by: Teutonic_Tamer on August 30, 2010, 03:38:58 pm
This sounds like the mechanical parking pawl is inadvertently locking, rather than the actual diff.  Maybe time for all DSG-ers to check the adjustment of the shift cable.

DomT - did yours occur whilst you were shifting the floor lever?  Got a linky to a relevent thread?
Title: Re: DSG Gearbox Failure
Post by: Poppa Dom on August 30, 2010, 05:26:12 pm
No, mine went when in drive doing 30 mph, but I think there was damage that then led to my failure as the diff was thrown out through the gearbox casing.
Title: Re: DSG Gearbox Failure
Post by: Teutonic_Tamer on August 30, 2010, 06:38:17 pm
No, mine went when in drive doing 30 mph, but I think there was damage that then led to my failure as the diff was thrown out through the gearbox casing.
But the diff bid for freedom could be an effect, rather than the actual cause, if you get my drift.

Diffs are generally increadibly reliable - and I haven't really heard of diffs locking to cause a failure.  For a gearbox (including the DSG) to physically lock up, then there are only really two causes.  Either more than one gear (ie two  :P) was selected on the same gear shaft, or unique to the DSG or conventional auto, the parking pawl inadvertently engaged on the crown wheel of the final drive (which also contains the diff).  However, with the latter, the parking pawls usually snap off - leaving two gears on the same shaft engaged - a possible mechatronics issue.
Title: Re: DSG Gearbox Failure
Post by: vRS Carl on August 30, 2010, 06:43:22 pm
Ouch bet he isn't impressed

Glad no-one was hurt though :happy2: