Torque converter clunk

[daviesbike]

Hi every one,

I am getting asked this quite often by customers 4.2 TDI owners and S8 owners who are saying when they come off the throttle and are just coasting as soon as they press the Throttle pedal they feel a clunk like the gear box is not engaged fully and there is almost like slack in the transmission.

After several D3 owners coming to me for a full gearbox service including rear diff oil, this dose seem to make it much less aggressive but dose not eliminate the problem all together.

Also After doing 4 lots of diff oil it shocking at how disgusting and burned it looks after just 60k

I am wandering if anyone else suffers with this and if there are any known solutions to the problem ?

[snapdragon]

Yes, on my 3.0TDI such as when lights turn green when approaching, especially downhill - I have sort of learned to drive round it by breathing on the throttle (so it is just off the 0% switch) and leaving it there for a second before pressing a bit more..

[daviesbike]

what causes this ? is it a bad torque converter ... or worn clutches .. or simply a software thing ?

[Mechcanico Lee]

I have felt this in my 4.2 tdi ....like you say in your first post like transmission slack ....perhaps part of the feeling is just that , it has a long driveline ....

autobox , front diff, front shafts, rear transfer box , prop , rear diff ...its got a lot to turn , but i reckon some of it could be cured with software changes and how the valve block bleeds over .

The S type and xj jags with the zf boxes i work on can have that 'slop' feel with them, with Autologic a software flash reduces this feel greatly ....its like you have fitted a whole new box ....makes them have a sharper response but still with smooth change over and minimum flare up between gears

[daviesbike]

Are you and auto box mechanic ? .. I'm looking for someone to map my box with the engine ..

[Mechcanico Lee]

Not a auto box specialist as such, been a tech for 27 years and work on models all types of repairs , ideally your looking for a mapping specialist .....how about Revo or Torx Tronics

[daviesbike]

il give them a try, I think il hook it all up to Our Gearbox machine First and change the fluids and filter from Life guard 6 to life guard 8 and then get the software flashed to the latest first and then take it to be remapped if that dose not cure it

we have all the kit but still have to go to Audi for the software flash

[Mechcanico Lee]

Originally Posted by daviesbike

il give them a try, I think il hook it all up to Our Gearbox machine First and change the fluids and filter from Life guard 6 to life guard 8 and then get the software flashed to the latest first and then take it to be remapped if that dose not cure it

we have all the kit but still have to go to Audi for the software flash

Yes, worth a go let me know how you get on , I just did a filter and oil
Change on my gearbox and re learned the adaptations , it did not make any difference to the 'slop' feel though .
I have a feeling that if you get it re flashed by Audi the file will be the same parameters for valve block control but worth a go .
The mappers may alter the duty cycles somewhat to make it 'sharper ' ..... I will ask my mapping man in Ireland .

[A8 Doc]

Let me know if you find a software update that works. I have Autologic and my D3 is on the latest software.

The only other rumoured software for the ZF6HP involves the blue fluid....

[a25c]

I am currently dealing with this exact problem and wondering has anybody any update on this problem?