2008 TT Tdi sounds different following service

[Br0416]

Hi,

I took my TT for a service 2 days ago. It had an oil change and all the filters done. But it also had the Haldex oil changed. Since the service was done my car isn’t running the same. It sounds wrong. When I get to about 3000rpm in 1st gear (sometimes 2nd also) there’s a really deep loud humming coming from the engine which makes the cabin vibrate. It only started doing this since the service and so it’s somehing they have done but I don’t know what to do. Please does anyone have any ideas on what could be going wrong?

Also when I get to about 40mph I can hear what sounds like a faulty wheel bearing which also only started since the service.

[Rob69]

Check the Haldex oil ASAP

[Br0416]

I’m taking it back to the garage but they seem to think they’ve done nothing wrong with the Haldex oil

[Br0416]

I’ve read that some people have experienced the rear differential oil being drained during Haldex oil change by mistake. Could this lead to the issues I’m having or would my car have broken down by now? I’ve driven about 60 miles since the service was done

[Rob69]

Yes - it sounds like you have some sort of transmission noise and vibration that wasn't there before, It could be wheel related, did they have the wheels off during this service or do any other brake or propshaft / driveshaft work, the propshaft runs along the top of the exhaust, have they had the exhaust off or anything related that might have disturbed the propshaft? does the engine vibrate standing still in neutral and revving it? . Depends what you mean by 'broken down' if you mean stuck at the side of the road then no, if you've only done low speed stop start driving, if you'd done 60 miles at 80 mph down the motorway then it would have likely put you on the hard shoulder. If I was you I'd avoid driving it any more and get it back to the garage to witness the Haldex and diff being drained, if no oil comes out then there's your trouble and new units required. If oil comes out then start looking elsewhere, find out exactly what this service involved and get under the car with them.