4motion - Which Variant

[Crowajingalong]

Hi all

I am new to the forum and about to purchase a 4Motion T6 with rear mechanical diff lock for a bit of outback travel. Can anyone please advise which 4Motion variant the T6 has - Haldex clutch, Torsen diff or lockable centre diff. I can’t find any info on it? Much appreciate.

 

[Loz]

See attached.

 

[Crowajingalong]

See attached.

Thanks Loz. Appreciate the reply. I am also looking for how 4Motion works on the T6. Is it full time, part time, all wheel drive? Can you switch it off? How does it work?

 

[Dellmassive]

pg 26 onward of the doc @Loz posted.

Power transmission The 4WD coupling generation V In the T6 2016, 4-wheel drive is offered in all vehicle variants with the following engines: • 2.0 l 110 kW TDI engine • 2.0 l 150 kW TDI engine • 2.0 l 150 kW TSI engine Optionally, a mechanical differential lock for the rear final drive is offered in all vehicles with 4-wheel drive. The differential lock has been taken from the previous model.

The 4WD coupling is integrated into the rear final drive. The 4WD coupling between the front and rear final drives controls the drive torque to the rear axle. It directs the required torque to the rear axle depending on the pressure in the multi-plate clutch. Structure and function The Haldex coupling of generation V is characterised primarily by a new pressure control.

The hydraulic pressure required for the 4WD coupling is generated by a pump with centrifugal force controller. This technology has allowed the weight to be reduced compared to generation IV of the 4WD coupling (Haldex) by 1.7 kg. The control logic in the various driving situations has been taken from generation IV of the 4WD coupling (Haldex), see Self-Study Programme no. 414 "4MOTION with 4WD coupling generation IV". The oil change in the T6 2016 is every 3 years or every 60,000 km. Please use the correct oil filler and drain plug! For more information, refer to the electronic service information system (ElsaPro). Flange for holding the propshaft Four-wheel drive control unit J492 Pump for Haldex coupling V181 Stone chipping protection

************************************************************************************

a diff-lock button will be on the dash for getting out of sticky situations ie mud/snow. but not to be enabled when driving.

the power delivery is ECU controlled as it monitors the ABS sensors for wheel slip,

 

[mmi]

As above +
The T6 4Motion has so called 5th gen 4Motion. The document below describes basic principles of the 4th generation system - which are still valid. The document is referenced in SSP561 as source of further studies (above).

SSP414 – 4MOTION with 4WD coupling generation IV. The document can be read and downloaded at 4MOTION | SSP 414 Online | Free Download

Basically full time all wheel drive but I guess it depends of your definition. I hope the document helps a bit.
There is no switch to turn it off. However, e.g. applying hand brake (turn hand brake warning light on) disengages it to allow some acrobatics. Of course just removing the fuse of the controller would disengage it - doesn't make any sense though.

 

[Crowajingalong]

T

As above +
The T6 4Motion has so called 5th gen 4Motion. The document below describes basic principles of the 4th generation system - which are still valid. The document is referenced in SSP561 as source of further studies (above).

SSP414 – 4MOTION with 4WD coupling generation IV. The document can be read and downloaded at 4MOTION | SSP 414 Online | Free Download

Basically full time all wheel drive but I guess it depends of your definition. I hope the document helps a bit.
There is no switch to turn it off. However, e.g. applying hand brake (turn hand brake warning light on) disengages it to allow some acrobatics. Of course just removing the fuse of the controller would disengage it - doesn't make any sense though.

Thanks all for the replies. My last car was a LR Defender, and very manual. Thanks again.

 

[Loz]

pg 26 onward of the doc @Loz posted.

 

[elliot330]

Thanks Loz and MMI, I learnt alot reading the documents. My summary would be... when you pull away and apply throttle, its 4wD. When cruising, its mainly fwd drive, when braking its fwd and if the ABS sensors detect wheel slip, its 4wd. Did i understand it right

Ref the diff lock function, is that locking the rear diff ( thus applying power to both rear wheels ) or locking the haldex coupling like the computer does when you accelerate?

 

[mmi]

My summary would be... when you pull away and apply throttle, its 4wD. When cruising, its mainly fwd drive, when braking its fwd and if the ABS sensors detect wheel slip, its 4wd. Did i understand it right

Short answer: Yes, correct. However I would like to say T6 is more full time 4wd than many regular passenger cars as Haldex coupling is tightened pre-emptively based on how you apply throttle instead of waiting wheel slip. I have noticed that on snowy roads I can accelerate at full throttle all 4 wheels definitely slipping but without traction control acting – thus there is no speed difference between axles for the ABS to detect.

Long answer: the fine details depend on –which engine and gearbox we are looking at.

I’m probably opening a can of worms by stating that there are remarkable differences how 4Motion works among different variants of T6. My investigations how 4Motion is implemented under different T6 engines ---> 4motion Abnormality And Subsequent Failure

Ref the diff lock function, is that locking the rear diff ( thus applying power to both rear wheels ) or locking the haldex coupling like the computer does when you accelerate?

Rear diff lock – locks mechanically rear wheels – absolutely no slip – solid connection. I’m not sure if locking rear diff also has an effect by ECU commanding even tighter Haldex coupling – as the coupling is already pre-emptively quite tight.

 

[elliot330]

Thanks for the reply mmi.. reading your link, I can see how you know how it works. Luckily for me, I have the 204ps DSG version and reading your summary, its ok right?

 

[mmi]

Thanks for the reply mmi.. reading your link, I can see how you know how it works. Luckily for me, I have the 204ps DSG version and reading your summary, its ok right?

Yes. So far so good . I do hope the upcoming software update won't change this