Hey guys,
I have a 2003 A4 3.0 quattro with 55k. I have had no problem with it since i bought it, until last week were i noticed a hard knock when i turn above 15mph. It knocks in both directions and i cannot get it to knock when im sitting still. I went under the car and inspected all the bushings and tie rods which seemed to be good. The car is very solid, but the knocking just scarres me. What do you guys think?
Thanks

 

That sounds like a CV joint going bad. You may want to make sure the boots are in good shape, and check for any play in the joint.

 

I second the CV boot and or axle..

 

Thanks,
I checked the boots ands theyre in good shape. How would i check for play while they are in the car?

 

Possibly a CV joint but I really doubt it. Knocking you say...possibly a single loud thunk, pop or as you say knock? My money is on one or more of the bushings where the upper control arms connect to their bracket. The bracket surrounds the top portion of the strut and mounts to the fender-well. I'll put money on it. I tried to find the link which has examples and whatnot of failing bushings but this might help nonetheless. Here you go http://forums.audiworld.com/tt/msgs/1551549.phtml

 

Ok cool, another opinoin!! Since im going to be doing the work myself, is there any way to tell if the bushings are bad other than prying the pieces together and look for excessive play?
Thanks

 

Not really that I know of. I have found that its actually a relatively common failure though. If your doing the work yourself be prepared to have quite a time removing the bolt that clamps the two upper control arms to the hub assembly. You'll be able to remove the nut fairly easily however removing that bolt is a chore to say the least. You might find that it turns a few times almost like its threading itself out and then it'll either snap the head of the bolt off or start to bend. Most likely both. If I were to do it over again I would get to the point where the bolt turns and then saturate it with a penetrating oil. Let that work for an hour or so, turn the bolt and again saturate it with penetrating oil. Repeat that a few times and you may, may get lucky and find that the bolt will be able to be removed. I wasn't so lucky and had to use a torch to heat the clamp and bolt in order to remove it. IT SUCKS. When you are reassembling I would replace the bolt and nut and then coat it with some anti-seizing compound so if your ever unfortunate enough to have to repeat the process it comes apart much easier. This probably goes without saying but should you find yourself in need of using heat to remove the bolt you may damage the boots on the ball joints of the control arms. Be prepared to have to replace all the control arms and not just the one that is bad. Its probably a good idea to do that anyways. Good luck man.

 

Thanks for the advice, im going to wait till spring when the weather gets warmer to start this project.