2004 - A6 Front end noise – help please

[midge6]

Hi,
I have a noise coming from the front axle (I can’t decide which side), it becomes noticeable from about 30 mph and increases progressively with speed. It’s nothing to do with the engine and is still there whether I have the car in gear or freewheeling. I have swapped the front and rear wheels and it makes no difference, nothing has been added to the vehicle recently and the only thing out of the ordinary is that I did a 550 mile round trip 3 days ago (I usually do shortish journeys), though, I didn’t notice any noise then. The noise doesn’t seem to change when cornering, though; it ‘might’ change slightly when I brake and I can’t detect any noticeable play in the wheel bearings. The noise is a consistent droning noise, a cross between a distant propeller on a light aircraft and a quieter version of the sound you might get when driving over a rumble strip. The only other thing that might be relevant is that ever since I have had the car (2.5 years – 20000 miles) I noticed a very slight ‘Click’ from the front when reversing the car in gear after about 8 feet – that seems to have gone now.
Anyone got any ideas or what else I might do to narrow the fault down?
Thanks in anticipation…
Midge.
Vehicle details:
2004 - A6 1.9Tdi Avant
63000 miles
5 Speed gearbox

[jonjosar]

It sounds like it could be a wheel bearing but it is difficult to diagnose even when you have access to the vehicle, let alone when its via a forum. A wheel bearing sound will increase slightly with speed and you will not find any play in the front wheel bearings(only there in severe wear cases). It might be worth having someone else drive the car and see if you can hear which side the sound is coming from.

[Peter D]

Yep Wheel Bearing I'm afraid. A garage put it up and ramps with the wheel off the deck and run the car in gear and listen to the hub assembly either through a screw driver or mechanics stethoscope. At home then jack it up use axle stands and check for movement in the bearing. If non then remove the wheels and run the car so you can listen to the hub assembly, however because there is no weight on the car it can be difficult to tell which side. Be very carefull doing this. Obviuosly the N/S is the suspect as it takes all the hastle on islands and all the pot holes. Regards Peter

[midge6]

Thanks guys, you were both right, it was the front nearside wheel bearing. I did as you said Peter, but for the life of me, I couldn’t hear where the noise was coming from. Knowing that it was more than likely a wheel bearing and that a press would be required, I decided to take it to my local Indy. He jacked each side up in turn, put the car in gear and got the wheel spinning off the ground – there was a significant difference in the bearing sound between both sides, so I was happy to let him repair it. This guy’s ok for the basics but I don’t have a lot of faith in him when it comes to diagnostics, hence my post here.
Thanks for your help.
Midge.