My '98 A-8 has recently developed a squeak in the left front end that I thought was coming from the strutt. The noise comes when the front left moves up and down and also during slight turns but does not make noise during sharper turns. A repair shop told me it was my front left ball-joints and they needed to be replaced.

I called Audi dealer for price for left front ball joint and was told the vehicle did not have them but instead had an upper and lower "control arms" with bushings. I stopped by a body shop that works on Audis and they looked up '98 A-8 front end in their parts book and they told me the bushings could be replaced. Called Audi dealer and they said ...could not but the arm needed to be replaced at the cost of $370 or so per arm. I asked them to check their parts list/drawings and low-and-behold...replacement bushings exist!

Both upper and lower bushings cost less than $150...what the heck.

The shop disassembled the front left side and put it back together without replacing anything because the bushings appeared to be in good shape and the noise went away upon re-assembly. I drove it for 20 minutes and the squeak returned.

The noise may be coming from the strutt...but one strutt costs $360+ and the shop tells me they should be replaced in pairs. What happens if I replace the strutt and the noise is still there?

I have lubricated everything I could find on the left end and the noise is still there. Any ideas?

It sounds to me like it's still the control arms. They should have replaced the bushings. It wouldn't have hurt - especially if they haven't been replaced since new.
The only other possibility is the wheel bearings, but I believe it's the CA's or their bushings. Audi CA's are known for having a short life.

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