Haldex pump clean at 20k miles

[KeteCantek]

Went for a haldex oil change plus pump (mesh filter) clean today and it wasn't as clogged up as I thought it would be. Thought I'd post this for reference/comparison purposes. 

 

20900miles on clock.

 

[newbie69]

Out of curiosity, how often are you using Launch Control? This doesn't look too bad but I have a feeling it also relates to the amount of AWD engagement apart from mileage and if there's any truth to that, with Dragy showing over 20 launches already I should be taking a look at mine soon...

[KeteCantek]

29 minutes ago, newbie69 said:

Out of curiosity, how often are you using Launch Control? This doesn't look too bad but I have a feeling it also relates to the amount of AWD engagement apart from mileage and if there's any truth to that, with Dragy showing over 20 launches already I should be taking a look at mine soon...

 

I have never launched it since I bought it used nearly 2 years ago precisely due to the fact that I know the pump has never been cleaned. 

 

Not sure what the first owner did so I cannot comment. 

 

That said, with dsg oil and this done, I plan to try out a launch when I get the opportunity. 

[J.R.]

The plate wear and oil discolouration is completely normal and not caused by "launches" quite the opposite in fact, were it possible for the Haldex clutch to be permanently engaged there would be zero plate wear or discolouration but the transmission wind up would probably break the guido coupling and/or the front transfer box.

 

There is always a small amount of torque transmitted by the Haldex and there will always be slippage of the plates (except under launch conditions) as the transmission does not have a centre differential, the front & rear axles follow different paths whenever the car is not steering straight ahead, even in a straight line there will be slippage (hence wear & discolouration) due to difference in tyre wear.

[KeteCantek]

2 hours ago, J.R. said:

The plate wear and oil discolouration is completely normal and not caused by "launches" quite the opposite in fact, were it possible for the Haldex clutch to be permanently engaged there would be zero plate wear or discolouration but the transmission wind up would probably break the guido coupling and/or the front transfer box.

 

There is always a small amount of torque transmitted by the Haldex and there will always be slippage of the plates (except under launch conditions) as the transmission does not have a centre differential, the front & rear axles follow different paths whenever the car is not steering straight ahead, even in a straight line there will be slippage (hence wear & discolouration) due to difference in tyre wear.

I believe with the gen V haldex, under certain low load conditions the rear is completely disconnected. 

 

What is true is that the pump is always working to pump fluid through the system and routing it as appropriate, more to the clutch if drive is required. That mesh forms part of the fluid path so if clogged, there will be fluid starvation and possibly even overheating of the pump as the fluid likely serves as heat transfer too. 

 

 

[J.R.]

No question about that.

 

Whether totally disconnected or partially engaged there will be slippage of the plates due to the lack of a centre differential which with the organic plate material will discolour the fluid and build up solids on the inlet filter screen.

 

My car has developed a noticeable transmission snatch sometimes when pulling away forwards after having reversed on lock, in both cases under an idling engine, no load to speak of so no Haldex engagement, I am not sure if its the plate pack sticking (I hope it is) or the first real sign of diff failure after having chosen the wrong hole

 

I think its the former because it does not snatch when driving on lock in either direction, has anyone else ever experienced it?

[KeteCantek]

@J.R. I don't think I ever experienced that. 

 

Heard lots of pump failure, not sure if diff failures are common or not. 

 

Guy at the garage said there was a TT-RS that had the haldex pump failed even with regular oil changes. However the pump filter was never cleaned

[Bap33]

On 08/10/2020 at 22:07, KeteCantek said:

@J.R. I don't think I ever experienced that. 

 

Heard lots of pump failure, not sure if diff failures are common or not. 

 

Guy at the garage said there was a TT-RS that had the haldex pump failed even with regular oil changes. However the pump filter was never cleaned

The slight detail that makes ALL the difference!  

[KeteCantek]

 

Last couple of minutes explains why it's good to keep the mesh clean. 

 

Summary: if it's clogged, significantly higher current is required to run the pump to achieve required pressure. Overworking the pump and control module. 

 

 

[ChrisCh]

Looks about right, I cleaned mine (and changed the oil) at 40,000 miles and it was about twice as sludged up as that - so looks like normal use to me.