Audi TT - AUDI QUATTRO haldex oil/rear differential damage

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Mon 13 Jun 2016 13:10
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - tt_driver

I have a 60 reg AUDI TT SPORT TFSI QUATTRO with 48K mileage. I recently had the car serviced at a VW and Audi specialist workshop per Audi service schedule. One service item was replacement of the rear haldex oil (first ever for the car). Two days (~50 miles) after the service I experienced a loud noise and loss of power whilst driving at speed on an A road. Luckily I was able to pull over safely and on inspection of the car by police and RAC the vehicle had suspected damage to the rear differential and was leaking oil. The car is back at the workshop that performed the service and I have been told the rear differential is cracked and needs replacement although the cause of the damage is unclear. I would like any thoughts to help understand what can cause such damage and how if the haldex oil change was maybe performed incorrectly this could in fact damage the differential to this extent. Anythng to help me have a knowledable discussion with the garage is greatly appreciated.

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Mon 13 Jun 2016 13:19
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - slkfanboy

Most likely caused by the hex bung being over tighten. These diff units are not as solid as you might think and can easly crack.

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Mon 13 Jun 2016 16:27
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - tt_driver

Most likely caused by the hex bung being over tighten. These diff units are not as solid as you might think and can easly crack.

do you mean the haldex drain plug? from what i understand this is separate from the rear differential unit so how could this cause the differential itself to crack? thx for any clarification...

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Mon 13 Jun 2016 18:38
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - John F

Another sad story of a manufacturer creating work in the form of frequent maintenance of sophisticated machinery (what was wrong with the good old maintenance-free Torsen system?) vulnerable to cack-handed British mechanics.

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Mon 13 Jun 2016 19:08
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - RT

Another sad story of a manufacturer creating work in the form of frequent maintenance of sophisticated machinery (what was wrong with the good old maintenance-free Torsen system?) vulnerable to cack-handed British mechanics.

Torsen-based 4wd systems have inferior fuel consumption to clutched 4wd, like Haldex and others, so less suitable for drivers that rarely need 4wd.

I have a Torsen centre diff in my Touareg, nicer to drive than Haldex, and economy less important in an expensive car.

Even Torsen systems need lubrication - so it depends where it's located and where it gets it's oil supply from/

Edited by RT on 13/06/2016 at 19:09

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Sun 20 Nov 2016 19:14
Audi TT - AUDI QUATTRO haldex oil/rear differential damage - Phillip Parr

Is there any follow up to this? I had the Haldex oil changed on my 60 reg TTS and managed 200 miles before the diff cracked. I've found a huge number of related incidents on various forums, but most of them are within warranty and so the forum runs dry...

What happened? Was the oil tested / confirmed? Was analysis carried out on the diff? Was it replaced because the garage was at fault? Was it replaced because the part is known to fail? Did you end up paying for it yourself?

Edited by Phillip Parr on 20/11/2016 at 19:15

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