Freelander 2 (LR2) Haldex

I have a leaking haldex,just topped it up after getting some knocking at low speed, took 600ml of fluid so nearly empty but knocking has ceased.
There’s a small 2mm hole on the underside near a slight indent about the size of a pinky fingernail on the diff side, , it looks drilled as it’s a clean hole but seems to serve no purpose except leaking the haldex fluid.
Any suggestions on this, I’ll need to fill with epoxy or metal filler ,but would like to know what it is or should it be there at all.?

I have seen similar where its a drain hole to indicate oil leaking into a part of a system/coupling that shouldn't have any oil in it .

Maybe oil is leaking into this space from somewhere ?

You may be right Kevm, probably a tell, might be a failed seal on the piston allowing fluid into the clutch casing. I had a refurb of bearings and seals a year ago, getting checked next week , guess I won’t be filling it in then

bfgquinn said:

I have a leaking haldex,just topped it up after getting some knocking at low speed, took 600ml of fluid so nearly empty but knocking has ceased.

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If you've filled it to the filler hole, like a traditional transmission, then it's over filled.
You're supposed to fill it, put the ignition on for 5 minutes, fill it again, then remove 70ml of fluid, which then sets the fluid correct level.

bfgquinn said:

There’s a small 2mm hole on the underside near a slight indent about the size of a pinky fingernail on the diff side, , it looks drilled as it’s a clean hole but seems to serve no purpose except leaking the haldex fluid.

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It's called a tell tail weep hole. It's job is to tell a repairer that fluid is getting past one of the lips on the seal. The seal is a labyrinth seal, which has 2 separate sealing surfaces, one for the diff oil, and the other for the Haldex fluid, the space between (the labyrinth), is in line with the weep hole, so seal leakage can be identified.
Normally if the seal is dripping gear oil, it's a sign the diff input bearing has failed.
Haldex fluid is leaking means the Haldex has suffered some form of failure.

Don't go filling the hole, LR didn't put it there by accident, it's there for a purpose.

bfgquinn said:

You may be right Kevm, probably a tell, might be a failed seal on the piston allowing fluid into the clutch casing

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It means the shaft seal is leaking, nothing to do with the piston, and the clutch is a wet clutch, so is running in Haldex fluid.

bfgquinn said:

I had a refurb of bearings and seals a year ago, getting checked next week , guess I won’t be filling it in then

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If the diff is a refurbished one, then the seal isn't installed correctly, or was damaged fitting it.
It should be fixed for nothing, by whoever refurbished the diff.

Nodge68 said:

Don't go filling the hole, LR didn't put it there by accident, it's there for a purpose.

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Nodge. I wouldnt go against your word as you are a legend on this forum and font of knowledge, but Interestingly when I took my FL2 to Austen at Bell Engineering to service my Haldex he filled the hole with sealent.

parxuk said:

Nodge. I wouldnt go against your word as you are a legend on this forum and font of knowledge

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I don't know about that.

parxuk said:

Interestingly when I took my FL2 to Austen at Bell Engineering to service my Haldex he filled the hole with sealent.

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What.
Is that correct?, I'll stop recommending Austin, if that's what he's doing.
The weep hole is there for a reason, and shouldn't be blocked.
Say the diff and Haldex seal fail, and there's nowhere for the leaking fluids to drain, then it's possible for oil from the diff to enter the Haldex, or the other way round. I don't think Haldex fluid would harm the diff in small quantities, but just a few ml of gear oil in the Haldex, will cause serious damage, which would then need a rebuild.

It's pretty standard for two components that use different fluids to have a labyrinth seal, or two separate seals, with a weep hole between them, so leaking can be identified, before fluids mixing can occur.

Blocking that hole isn't correct at all.