I have a 1996 A4 2.8 5 spd. When I am driving between 45 and 55mph with the rpms between 2300 and about 2800 I hear a pulsating sound like a low bass. It is not unbearable but is annoying. Oh and it is the worst in 4th gear. Actually I cannot hear it unless I really listen for it in any other gear but 4th. Is it my engine or tranny? is it normal. Any body have any suggestions?

 

Somebody's gotta know! Please

 

where does the sound come from? Wheelwell? If so it could be the start of a bad wheel bearing. Might just be tire noise.

 

Ditto what brrman said.

Where is the noise coming from?

My first guesses would be wheel bearing or tire.

 

I really cannot tell where the noise is coming from. I want to say right in the middle, like where the driveshaft might be. I really just hear it pulsating everywhere in the cab. If I move my head to a different part of the car while it is making the noise, I hear it just as much as when I am just sitting there. My boss thinks it may be a bearing in the driveshaft. Maybe????

 

Yup def a wheel bearing. I had the same problem on mine. Don't wait to long to get it fixed or you could damage your hub.

 

if its that bearing in the middle not to scare you or anything but that bearing is not replaceable we have have a coulpe of cars here with that problem even though they were older ones but there is a place in the States that rebuild them can't think of the name you don't want to have to replace the prop shaft though thats big $$$$$