KVDZV

I know that the control arms are a common issue. I have a 2008 A8 L that rides like trash. I can feel everything in the road. The steering isn't great. The compressor was replaced last year and the left front control arms were replaced in July of this year. The air struts are good, no faults or leaks. I don't see any issues with the bushings for the upper control arms on the front.

The more i drive it, the more it seems like the sway bar bushings may be bad? It's just rough. It doesn't clunk or shake. It doesn't bottom out. It just rides rough. It feel loose.

Anyway. I'm just looking for what the common symptoms of various bushings going out would be.

MP4.2+6.0

1. Have you visually inspected the upper control arms, including removing pinch bolt to move them around more on the bushing side?
2. How many miles on car?
3. Why only one upper control arm replaced apparently, among the four to be clear? (Hint: #2 is likely to inform this one). Not sure I understand your post correctly, but is it also saying both the upper and the lower arms were replaced in front on the driver's side?
4. Was car aligned after control arm replacement? Is it showing wear on inner edges of front tires, either pre alignment and control arm replace, or now? If so, one side, or both?
5. Have you visually inspected the sway bar links? Not the bushings that bolt the bar to the subframe, but rather the U shaped links at both ends. Yes, bushings can fail, but so far it has been generally the early ones and accompanied by noise. Diagnostic there is either silicone sprayed in and/or pulling the saddle clamps and visually inspecting. Link failure far exceeds bushing failure judging from a dozen years of threads here.
6. Have you checked tire air pressure? And, with a 2008 (as opposed to 2006 or earlier), you realize the dumbed down sticker on the door jamb only refers to the max load pressure? As in, stiffer ride result. See the owners manual for the pressure choices, including partial vs. full load.

KVDZV

1. I have not removed the pinch bolt to move them around. I'll give it a shot.
2. 130k
3. One left forward control arm and two left rear (upper and lower) control arms is what was on the receipt from the shop.
4. It was aligned. There is no uneven wear. The front tires have no visual extra wear on the inside of the tire (BUT the front left inner fender cover is worn from the inside edge of the tire touching it. It looks like the control arm that was replaced stopped this as the tire no longer touches that area).
5 No i need to remove all 4 wheels and check all the sway bar links. I know the U shaped links you are talking about.
6. Tire pressure is good. I've tried a few different pressures and had no improvement.

Thanks for your ideas. I'll take a closer look at the sway bar links and bushings this weekend.

MP4.2+6.0

So, at 130K miles I would say the presumption should be that your right side upper control arms (front and back) are both bad. Inspect to see if it is otherwise. I think max life even on OE is maybe 100K--probably only corner cases of the proverbial little old lady driving 55 only on the highway could commonly get beyond that. The car, wheels and brakes are all overweight for the characteristics of the mid 90's A4 design that is fundamentally at work here. By 130K I was/am on my third set--careful monitoring and for first set done under warranty. W12 weight and power, but that isn't radically different and endless posts I think support the 100K type common max miles to maintain ride. The left side damage is pretty odd BTW. Those must have been seriously torn out, or maybe even accident damage or shredded tire or something. Regardless, the bushings are done once seriously cracked, and if torn out are way overdue/screwed up.

Likewise by 130K I would assume your front sway bar links are also done. The Lemforeder OES is now so cheap it isn't even worth guessing. $18 each, here: https://www.rmeuropean.com/Products/...G69-V1394.aspx So cheap you now have to buy two sets to get their free shipping deal. Their prices are also good for OES (again Lemfoerder) for upper control arms. Links are now absurdly like 10x that at dealer, and control arms probably twice at dealer list. Can also go the bushing route if your shop/you are equipped for that.

Also consider tires. More than a few over the years had tires with good apparent tread life left, but that weren't up to snuff and affecting basic ride. Noise sometimes forced a change, but other times folks only realized it fully when they got new ones.

Inspect all, but at least at price of front sway bar links now and your general description, that would be on my no brainer short term list. Very easy to change too.

KVDZV

I have an appointment with Audi tomorrow for the catalytic converter recall. Which i'm not super excited about. However, i'll have them quote the suspension work that needs to be done. Then i'll just order what they quote and swap it out and take it back to them for an alignment.

KVDZV

Also, the tires are the Pirelli Cinturato P7s. I just realized these are run flats. I imagine this could contribute to a rougher ride.

MP4.2+6.0

Yep. Job 1 when I got a Mini (like most all BMWs) was to summarily remove the Run Craps.

Sci-fi_Wasabi

Are the front sway bar links under any kind of tension, like if i have one side of the car jacked up and the wheel off, is there some kind of torque on the sway bar that will cause it to twist as soon as i take the link off? Do i need to have right and left sides off the ground....
just trying to not impale myself.

MP4.2+6.0

They are under tension when one side is jacked up, since that is essentially like corner lean that the bar is set up to resist. Thus, either use ramps to get under, or jack up both sides. If you loosen it with one side up in air only, it will pop some as you back the bolt all the way out, may mess up threads, but also be very difficult to get back in until both wheels are either supporting similar weight or up in air together.

Sci-fi_Wasabi

makes sense, good advice. I'll take the time to jack up both sides then. thanks