I replaced the tires that were on my 01 a4 1.8t quattro avant for excessive wear on the inside shoulder of the front wheels about 10k after I bought it. when i got the new tires i had an alignment done. now 30-40,000 miles later I am seeing the same wear pattern. i have rotated them but probably not as frequently as I should be. I am guessing I have a worn suspension or steering part that is causing this tire wear.
Any suggestions on what would cause this type of wear?

Our cars come with negative camber from the factory (on purpose), which you cannot adjust. You can adjust it somewhat, by moving the sub-frame, but if the tires are wearing evenly, then the sub-frame alignment is fine.

Factoring that in, I would also check:

Tire pressure (All tires should be at 32psi - cold)
Worn suspension components (coil overs, control arms, etc.)

G/L

when you say control arms worn, i'm assuming you mean the ball joints and/or bushings in them?

Yes I do believe that's what he is referring to. Usually most (if not all) of us replace the entire control arms as it's generally easier and still cost effective compared to replacing only the bushings / ball joints.

Work tie rod ends can also contribute, but if this were the case you might notice "sketchy" driving.

actually the car does wander a little bit, especially on off camber roads, it pulls downhill.

Definitely try to see if the tie rods need replacement; it can be dangerous if they're worn.

To test them: with the car off the ground, grab the front wheels at 3 and 9 o'clock, and push/pull. If there's any movement then it's time to replace tie rod ends and get an alignment.

If the bushings are bad, then it will wander around and you'll never be able to get a proper alignment to stay put.

I recently replaced all 8 of my control arms, steering rack and all 4 tie rods.

And.....It just so happens that I have a brand new set of (complete) heavy duty upper control arms, ball joints and (almost all of) the hardware you'd need to do the replacement, sitting right next to me - boxed up and ready to be shipped (I have them listed on eBay).

The only reason I have this stuff is because they are extras (I accidentally bought too many). Everything's brand new.

If you really need them - and you want them, I'll give you everything for $70 plus whatever it costs to ship it all to you.

Here they are:

thanks for the offer but im just gonna order the full control arm kit and tie rod end kit offline.

seems like the consensus is to replace the upper control arms,
why not the lower and trailing arms as well?

There is no reason not to replace the lower arms, you should replace all of them at once. You're going to be in there anyway and are already going to be paying for an alignment. Do them all.

Usually the full kit is referred to as 12 pieces. 8 control arms, two tie rods, and two sway bar end links. I would recommend the Meyle HD kit.

Or you can just have seized tie rod ends like me and then you're unable to get an alignment.