Replaced my pump and filter today, I picked up the four sealing bolts from the network and thought I would get another bottle of oil to allow me to flush the oil crud from the system all placed in a bag which I didn’t check until doing the job. To my horror the parts person had supplied me with the rear axle oil in spite of my asking for Haldex oil.

please check you get the correct oil for the job you want to do as if I blindly filled the system with the oil I was supplied, that would be the end of my final drive plates.

As it happens I didn’t bother taking it back as I changed the diff oil too.

For someone that wasn’t aware of the two oils used in the housing it would have been a big problem.

The pictures show the correct oil for Haldex in the white container and the diff oil in the grey container, take note of the part numbers and make sure you get the right one for the job you want to do.

The Haldex ecu needs to be removed to gain access to the pump and power supply plugs. Just two Allen bolts hold it to the housing. Careful reinstalling to line up solenoid contacts correctly. Haldex V shouldn’t need the ecu removal to unplug pump connector. 

Also no need to loosen the subframe bolt as instructed in ELSA if you use a picece of wire to guide the pump loom.

Edited 19 May, 20197 yr by 3T1704X4
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If you are changing your own pump don’t cut the wire as the instructions suggest, it’s easy to remove the retaining clips (yellow arrows on bottom picture 3x retainers simply push into holes)  and just use a piece of wire tied to the old plug and feed through, tie the new plug to the wire and gently guide it across the housing. The retainers may get caught up but simply space them out and push into the three small holes. You can then strip your old pump and replace the carbon brushes for the next time it fails then just swap between the two.

Slightly over fill the Haldex then run the pump and actuator final control three times leaving pump running for two mins each time to get rid of air in the system.

 Then either let the pressure out of the oil pump and allow the oil to drain back into the container or just remove the fill pipe and allow the oil to find its own level.

If you have dumped the diff oil too, DO NOT FORGET TO REFILL. They last about 40 miles before the diff spews it’s guts on the road.

I have seen this happen twice where a service agent drained the wrong section or simply topped the wrong one up. Oops.

 

Oh another tip, to get the filter out without struggling, don’t drop the oil or pump first, your first job I suggest is remove the cover bolts and aluminium cover for the filter, run final control to operate the pump ( mine was showing static open circuit so had to tap the pump housing a few times to get it to work) this pressurises the system and forces the white filter housing out along with some oil, stop the pump. You will struggle much more than you need to without doing this. Once the white part with the two O rings is out, the filter can easily be retrieved. Then dump the oil and the pump.

If you can’t get the pump to run, fit the new one and use the hydraulic pressure to help you.

Edited 18 May, 20197 yr by 3T1704X4
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Nice write up thanks.

I am still amazed that VAG don't recognise the proper servicing requirements of the Haldex system.

My local dealer wasn't really interested in hearing the detail and when I was looking for an independent specialist to replace my pump last year a number of the VAG specialists I contacted didn't know about it either.

I am pleased to have found a company fairly local that know what they are talking about when it comes to Haldex !