I’ve just removed my gen 3 haldex on my FL2 2007 (150k) and I’m a bit confused why there is a lack of oil anywhere?

I sucked about 40ml of oil out of the filler whilst it was on the car and when I split the haldex from the rear diff I was expecting oil to drop but not a drop came out! Should I be worried about this or not? A few of the guides I’ve read suggests oil will spill out but I had none. I haven’t removed the pump or filter yet so I know there should be some in there hopefully!

Also when I removed the haldex it seems to have removed the big bearing from the rear diff with it. Is this ok? As a few photos on here do not show this. ( once 4 bolts for haldex was removed it was quite difficult to remove I had to get a hammer as it was almost stuck solid. I have attached a few photos. Thanks!

Haldex holds about 650ml.
Any evidence of a leak prior to removal - around the big rubber O ring maybe ? Jules

Sounds as though you were low on haldex fluidl!

If its anything like the gen 4 then there is no way you would have removed the diff bearing. If you are referring to the big silver round thing in your photos, that is the clutch pack and is part of the haldex. FL2 HSE Auto Galway Green
Evoque SD4 Auto Blue.
FL1 HSE TD4 Manual Black - Gone.
RR Classic V8 EFI - Gone

Yours looks very grimy - dirt in oil maybe.

Mine was bone dry and fairly clean on the outside at 5 years old. Jules

Thanks guys for your thoughts!

I removed the pump and the filter and they were both clogged with thick sludge. Couldn't believe how thick it was! It was quite grey looking sludge. I did notice a slight nick in the haldex-diff big o ring so I suspect water has got in and emulsified the oil and thickened it all up thus why I had a lack of oil. I was not confident enough to take apart all the plates on the bearing so I left and tried to blow out any debris with an air line.

I had about 3 ohms on the motor and I ran it both ways on a battery so that seemed ok. I've only had this FL2 3 months so I've spent a lot of time doing all the usual maintenance but how do you actually test that the haldex is working? The 15a fuse is ok but I can't understand how this thing could run dry? I thought about putting the car on 4 axle stands and running it to see if all 4 wheels spin but that would be normal operation right? (Plus it's an auto so that wouldn't work) Because all 4 wheels would have drive in a normal situation and all the haldex does is apply more or less torque to the back wheels?

Do I need to try and wheelspin on gravel or something!?

It looks oily on the outside so I’d say that’s where your oil has gone. I’d consider changing that pinion oil seal while it’s out. Past: FL2 TD4 HSE Auto
Evoque SD4 Dynamic Lux Auto
Present: Audi A3 S Line.

kiwiNCFC wrote:

Thanks guys for your thoughts!

I removed the pump and the filter and they were both clogged with thick sludge. Couldn't believe how thick it was! It was quite grey looking sludge. I did notice a slight nick in the haldex-diff big o ring so I suspect water has got in and emulsified the oil and thickened it all up thus why I had a lack of oil. I was not confident enough to take apart all the plates on the bearing so I left and tried to blow out any debris with an air line.

I had about 3 ohms on the motor and I ran it both ways on a battery so that seemed ok. I've only had this FL2 3 months so I've spent a lot of time doing all the usual maintenance but how do you actually test that the haldex is working? The 15a fuse is ok but I can't understand how this thing could run dry? I thought about putting the car on 4 axle stands and running it to see if all 4 wheels spin but that would be normal operation right? (Plus it's an auto so that wouldn't work) Because all 4 wheels would have drive in a normal situation and all the haldex does is apply more or less torque to the back wheels?

Do I need to try and wheelspin on gravel or something!?

Steve D wrote:

It looks oily on the outside so I’d say that’s where your oil has gone. I’d consider changing that pinion oil seal while it’s out.

Read the below for additional info...
It's for Haldex 4, but some principles are the same...

https://www.freel2.com/gallery/albums/user...x_gen4.pdf

thanks Alex Jules

You're welcome and also sorry for the OP that I didn't find info on Haldex 3, as he has...

Thanks for the clarification Jules.

Thanks also for that document Alex, very detailed.

So, if I wanted to 'test' the haldex how do I go about it? I am just concerned because my haldex had no oil in it I am unsure if it had damaged the haldex ECU (fuse has not blown but I understand only takes about 5a to blow the ECU).

According to that document haldex becomes active at 400rpm so as soon as the car starts up it should be active. But how can I test? Would any garage diagnostic equipment be able to see if it is working and is up to pressure? Otherwise how do people know that there haldex is working or not? Do they just assume?

@kiwincfc

As an additional note when I removed my haldex it looked like this



at 4:37

Yours appears to have a smooth shiny outer sleeve - never notice that on mine (gen4) Jules

kiwiNCFC wrote:

Thanks for the clarification Jules.

Thanks also for that document Alex, very detailed.

So, if I wanted to 'test' the haldex how do I go about it? I am just concerned because my haldex had no oil in it I am unsure if it had damaged the haldex ECU (fuse has not blown but I understand only takes about 5a to blow the ECU).

According to that document haldex becomes active at 400rpm so as soon as the car starts up it should be active. But how can I test? Would any garage diagnostic equipment be able to see if it is working and is up to pressure? Otherwise how do people know that there haldex is working or not? Do they just assume?

Yes I did wonder why my big bearing was smooth and not covered in grooves like the above video. There are not a lot of videos showing gen3 Haldex’s online. I hear that the gen4 was much improved and was used for a lot longer than gen 3s. Obviously on the FL2 it was only the early models that had it.

That’s a great shout about the wheels. I will give this a go when I get it all bolted back together and let you know ! 😁