DSG gearbox - technical explanation required please...

[kingbilly]

Got a small problem with my DSG upshifts in Tiptronic mode, using the gearstick (no paddles).  Sometimes get a bit of a jolt/clunk when upshifting, mostly from 2nd to 3rd.  Can't quite tie down a pattern or trend.  Not always when engine cold or under hard acceleration.  Possibly on an uphill is the only consistent time.  Upshifting in D mode is perfectly smooth as expected.

The car is a 2005 model with 47k miles, and never had the gearbox oil changed.  Everyone I speak to obviously recommends an oil change, but at £280 I am not convinced this will solve my problem.

Please can someone explain what the difference is between shifts in T and D mode.  I am assuming that it is all electronic, which is why I can't get my head around the oil being my problem.  Or is there an element of mechanics involved in the T mode.

Any info greatly appreciated.

Billy.

[Hurdy]

Just like anything else, the DSG oil degrades over time and use.

At 47k miles you should have had the car in for the DSG service by now anyway. I understand that £280 is a substantial amount to pay for a service, but the oil itself is around £13 a litre and it takes about 7 litres.

By T mode I'm assuming you are referring to tiptronic/manual mode yes?

When using the manual upshifts they are faster than in D mode and that is about it.

There are a few more threads in the MKV section on DSG faults and one or two have "clunky" shifts a little like yours. Not everyone looks in here, so you may be better off posting in the main MKV section (Or I can move this for you if you want!).

[kingbilly]

Hurdy,

Thank you for your reply.  Don't get me wrong, I will gladly pay £280 if the problem is guaranteed to be fixed.  It's just happening in Tiptronic mode from 2nd to 3rd.  If it happened from 3rd to 4th, 4th to 5th, or in D or S mode, then I could understand the answer being oil.  Why would an oil issue only occur from 2nd to 3rd.

I did post in the main section, but the only replies were, get an oil change.

I would like to understand the workings of the gearbox first and be convinced that an oil change is the real answer.

Regards,
Billy

[Hurdy]

If you look at some of the threads, a clunky shift could point to the mechatronic unit being faulty. It could be quite a few things, but until you start to eliminate things one by one you don't really know for sure.

[Teutonic_Tamer]

Just like anything else, the DSG oil degrades over time and use.

Agreed, but more importantly, the clutch friction linings and gear synchro rings wear out, and those bits of 'wear' are carried all round the box by the oil.

At 47k miles you should have had the car in for the DSG service by now anyway. I understand that £280 is a substantial amount to pay for a service, but the oil itself is around £13 a litre and it takes about 7 litres.

Actually, intial factory fill is 7.2 litres, but on a routine DSG oil change, it should only use approximately 5.5litres - so if you were charged for 7 litres, I would be asking for some money back! 

By T mode I'm assuming you are referring to tiptronic/manual mode yes?

When using the manual upshifts they are faster than in D mode and that is about it.

Hmmmmm, cant really agree with that.  Provding that the correct cog has been correctly pre-selected, then upshifts will be identical in time irrespective of being in D, S or tiptronic modes.

There are a few more threads in the MKV section on DSG faults and one or two have "clunky" shifts a little like yours. Not everyone looks in here, so you may be better off posting in the main MKV section (Or I can move this for you if you want!).

In all honesty, it is vital that the OP gets the oil and filter in the DSG changed ASAP.  If the fault is stil apparent after that, then you need to be looking at getting the DSG re-adapted, and also make sure the DSG ECU has the latest software map.

[RedRobin]

^^^^
So when was the last DSG software map update?