06 Drive line issue

Hello, I have a noise from my 2006 Jetta 6 speed auto and I’m wondering if anyone else has had similar problems.

Got a noise from front of vehicle, sounds like wheel bearing noise but isn’t. I was pretty sure it wasn’t wheel bearings so handed it to local garage to check out. They got back and said they had put chassis mikes on car and my front passenger wheel bearing was needing replaced. They changed it and noise was still there. After discussion we drove car with mikes still attached close to each wheel and one mike on gearbox. The noise coming from the car speeds up and down with the cars speed. Whilst driving on a straight road we shut of engine and had car in neutral. Noise was still there. I’ve jacked up front wheels and ran the car and noise is there so it’s ftom drive line in front. Now I’ve just replaced the other front wheel bearing and noise is still there. I’m thinking either drive shafts or bearing in gearbox, although noise cannot be heard from gearbox with chassis mic attached to it. I also looked at brakes but they look ok and no vibration through pedal or steering wheel. I’d welcome any ideas.

Thanks Dave

Have you ruled out tires yet? Swap them to the rear if you see any uneven wear.

Spinning the wheels while airborne would rule out the tires themselves.

Have you tried jacking up the front wheels individually to rule out bearing noise?

Thanks for the reply’s guys. Noise was there with summer tires and still there with winter. As 325 Guy says I jacked up front and noise was there. When I had front end off ground I’m couldn’t hear the noise outside the cabin only inside with doors shut. Spinning each wheel separately by hand doesn’t seem to give anything away. When you say bearing noise are you thinking bearings on output side of gearbox? When driving car the noise grows with speed but does not change with gears. Even if I put in tiptronic and go through gears at same same noise does not change. Only changes with speed. Hope this helps

I was actually thinking an improperly preloaded wheel bearing. But, if the wheel bearings were at fault here, you'd clearly hear them at the wheels if you're spinning the wheels in the air.

Is there any evidence of a DSG fluid leak?

It’s not the wheel bearings, I’ve still got a rear drivers bearing sitting on my bench to install but as said before noise is from the front. It does sound like a wheel bearing hence when I handed it to a local garage for an examination their mechanic went straight for replacing the front near side wheel bearing even though I told them I believed it was something else. I’ll check for leaks today I think there’s an oil leak sure I’ve seen some drips on the garag floor but looks more like engine oil. I was thinking there’s a leak from up top and running down block. I’ll look today and see what I can find. Thanks again. I don’t think it’s leaking from gearbox where the driveshafts enter.

The leak may well be engine oil. The BRM valvecovers can leak either from the valve cover seal (fixed by tightening the bolts in most cases) or from the injector harness seal.

If it is an DSG oil leak, you'd have to complete the DSG oil replacement procedure, since there is no fluid dipstick. Even so, if there's enough oil loss to cause noise in the geartrain, there is likely already some damage there. As for the wheel bearings, you've eliminated those...I wonder if spinning the wheels individually would let you narrow the noise down to either an output shaft bearing, which you'd only hear when the bad bearing is spinning, or something else in the gear train.

Unfortunately, any of those options will require the transmission to come out for service unless adding fluid magically stops the noise somehow. It may be worth it to source a replacement DSG at that point. How many miles are on this one?

I’m sure the cars about 200,000 Kim’s on the clock. I’m sure it’s going to be a bearing on output side but the garage who inspected the car said wheel bearing straight away and went for easy option instead of checking properly. After relacing passenger wheel bearing which wasn’t the problem they did remount the chassis mic’s and I went out for a listen. They stated that they had mic on gearbox and when speaker was switched on to gearbox mic the noise could not be heard? So they still think it’s something else.