Haldex breakdown

So, my Haldex went out and bought a used one. Unfortunately my used one didn't make it through the clutches of UPS shipping unscathed. One of the mounting points were broken. Well, from what I was told my the dealership I only needed a clutch/clutch pack, Part #: 0CQ-525-554-T So I decided to just remove the clutch from the used Haldex/differential and then open up the differential to see what is inside. Supposedly this used differential has less than 300 miles on it. If this is true, I'm worried what I'll find when I open mine up.

Are you past the warranty period or did the dealer deny coverage?

They denied warranty coverage. The previous owner had an ECU tune at some point. It sure as heck wasn't on there when I bought it! Lol. I begged and pleaded, said it wasn't me, how would I know since they're the only ones that have the tools to check for TD1. Then I asked if there is anyway they could check to see when it when it flashed and they said no. They can only see that at one point it was modified. I have more important life things going at the moment to fight with Audi. But this will probably be my last VAG car. I've been burned by them far more times than I've been helped by them.

As it stands right now, the engine operates with no issues. I did perform the increased traction for the Haldex mod. I can definitely say, it works. Before I did the mod, I was getting no traction since the Haldex was dying. It was a 300HP front wheel drive. Loss of traction at pretty much any hint of aggressive acceleration. But after the increased traction mod, I can accelerate somewhat briskly without a huge loss of traction. If I floor it, I still get some traction issues. But I would say, it's similar to a stock GTI now. Not what it used to be, but I can say that the VAG-COM mod works without a doubt.

Sorry to hear. The most common failure points on these is the pump which can be bought/installed for $500 or so.

Thanks. Yeah, it does suck. My warranty expires September 1 and I was definitely gonna be going Stage 1 or 2 shortly thereafter. The Haldex probably would have failed anyway and I'd still be in the same situation I am now. Screw Audi but o well. Life goes on. Lol

The pump can be bought for $138. I just bought one on Ebay last night. And shopdap has it for like $150 shipped.

I'm no mechanic, but here's my opinion. The Haldex is failing due to the pump screens getting clogged and no fluid is able to make it through to keep the pump cool because there isn't enough hydraulic pressure being applied to the clutches. Which in turn causes the clutches to grind and slip causing debris to clog up the pump.

I say that because if you look the revisions of the Haldex units, the clutches have been revised and the differential has been revised but the pump itself no revisions.

When there's insufficient pressure the clutches can't lock, so I'm not sure how you can burn up the clutches. Looking forward to see what yours look like.

I'm saying the pressure is sufficient enough to move the clutches close enough to touch but not sufficient enough to effectively grab on to one another. So they just graze one another.

I think that maybe that's what the Haldex VAG-COM mod is doing, increasing the pump pressure. Because how else could I have gained back lost traction after performing it?

liljonny16 said:

They denied warranty coverage. The previous owner had an ECU tune at some point. It sure as heck wasn't on there when I bought it! Lol. I begged and pleaded, said it wasn't me, how would I know since they're the only ones that have the tools to check for TD1. Then I asked if there is anyway they could check to see when it when it flashed and they said no. They can only see that at one point it was modified. I have more important life things going at the moment to fight with Audi. But this will probably be my last VAG car. I've been burned by them far more times than I've been helped by them.

As it stands right now, the engine operates with no issues. I did perform the increased traction for the Haldex mod. I can definitely say, it works. Before I did the mod, I was getting no traction since the Haldex was dying. It was a 300HP front wheel drive. Loss of traction at pretty much any hint of aggressive acceleration. But after the increased traction mod, I can accelerate somewhat briskly without a huge loss of traction. If I floor it, I still get some traction issues. But I would say, it's similar to a stock GTI now. Not what it used to be, but I can say that the VAG-COM mod works without a doubt.

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Who did you buy the car from? What is a CPO from the dealer or the dealer passing this car as off as still being under warranty?

You should be able to email tuning vendors to see if your car was tuned and get a date of when it was tuned. I guess it's too late now but I'm just curious if a dealer is trying to sell you a tuned car without disclosing that fact...not that it hasn't happened before.

I bought it from a Chevy dealership. Someone traded it in for a Malibu. There's no way they would have known if the person trading it in didn't disclose it.

liljonny16 said:

I bought it from a Chevy dealership. Someone traded it in for a Malibu. There's no way they would have known if the person trading it in didn't disclose it.

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Gotcha, understood.

Am I the only one thinking about making a solid shaft to replace the clutch unit?

To the OP, it looks like that unit came off a car that was involved in a severe wreck, so who knows what it experienced and how long it has been sitting.

SomeDude said:

Am I the only one thinking about making a solid shaft to replace the clutch unit?

To the OP, it looks like that unit came off a car that was involved in a severe wreck, so who knows what it experienced and how long it has been sitting.

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Making a solid shaft sounds like a sweet idea. I wish one of the tuners would look into something like that.

And yeah, the car was in a pretty bad front end wreck. I'm not overly concerned after the clutches being damaged due to that. But I'll find out this weekend if they are or not when I take mine off to compare.

**Update**
Drain the fluid and took off the stock clutch and pump. I did service at 32K back in February and I'm at 36.5K now. I think the dealership drained the fluid earlier this month because they did say the pump screen was covered in debris. After looking at the stock unit vs the used one. Mine appears to be in much better shape.

In the back of my mind, my goal was always for this to be a temporary fix and I was just going to replace the entire differential sometime next year but I was hoping to get lucky and this might turn out to be a permanent fix. O well. I'm going to try them both. And I'll update you all with my findings.

liljonny16 said:

**Update**
Drain the fluid and took off the stock clutch and pump. I did service at 32K back in February and I'm at 36.5K now. I think the dealership drained the fluid earlier this month because they did say the pump screen was covered in debris. After looking at the stock unit vs the used one. Mine appears to be in much better shape.

In the back of my mind, my goal was always for this to be a temporary fix and I was just going to replace the entire differential sometime next year but I was hoping to get lucky and this might turn out to be a permanent fix. O well. I'm going to try them both. And I'll update you all with my findings.

Click to expand...

Great thread, thanks for the pics and info!

My 2015 R with 23k miles is getting the replacement clutch under warranty (Same Part #: 0CQ-525-554-T) rather than the whole rear diff as many have gotten under warranty...

However, the more I read on the "haldex failures" the more I'm getting the feeling it's just the haldex coupling pump (v181?)

Is that the part you replaced?

Is the pump included in the clutch assembly? (0CQ-525-554-T)

That's what I'm trying to figure out now.

And is the whole rear diff not required, or does just replacing the clutch suffice? Lots of conflicting info out there. Guess it depends on your particular case.

Again, thanks for the insight and detailed posts! Really helps others with the same problem.