MP4.2+6.0

Not enough experience yet, but mine are fine at 60K + miles on 2015 575 HP S8 (true stock power per APR dyno). Start with the front sway bar links. Already done mine back by 50K and owners report those as earliest to go on D4--versus the upper control arms on D3. Just find the Lemforder ones with the aluminum dogbone (different shape than the U links the D3) and be done with it. <60 minute bolt in, both sides. No more early creaks coming to a slow stop when cold--which from most reports start here. What mine had faint signs of if I left tunes off and drove like grandpa. New links and all good. If you knew D3, watch for it in tires too; the front upper bushings would grind off the inner edge of tires if worn. D4 design there is still similar, but another size up on the bushing end. Per my D3 posts, you really can't be 100% sure on those upper arm bushings unless you unbolt ball joint end and then rotate them around bushing end while looking for deep cracks, play or any noises.

RobertISaar

Oddly enough, no real noises that I'm noticing, it's just the upper control arm bushings are visibly falling apart. I put my borescope under the car while at typical ride height to get a better idea of how they look in operation, the core sections are either separated or on their way out on all 4. The inner edges of the rear tires are on their way out, unknown distance on them and I'm sure they were rotated there. I only started looking around once I started noticing the steering wander when there was definitely no reason for it to be happening, that was always the indicator on my D3 that they needed done. If they're up sized on the D4 and do last longer, I can reasonably go with more OEMish rubber and not worry about them again for quite some time. I don't really remember the poly units adding noise to my D3, but I could certainly feel what the front end of the car was doing better. With the rack being low mounted on the D4, I wonder if that changes anything?

I don't remember specifically looking at the sway bar links, but I can poke around there again when I have the car in the air to change the 8HP fluid.

MP4.2+6.0

I do remember one guy on D3 board who did Poly and was first positive on them later saying he had some noise eventually. Another few posts I sort of remember that didn't sound good causing me to take note to self, no poly. No memory if it was someone else or you. Just from being here a long time now, D4 board has a lot fewer squeaky and creaking suspension posts and strut issues than D3, though not as many hard core wrenchers at similar respective vehicle age either. They are most commonly the front sway bar links first. Like D3 I suspect as these age the lowering modifications some do may get conflated with strut issues, but fortunately not a lot of strut posts so far, and then almost no tired compressor posts.

If not aligned yet, a possible step. All recent Audis I have had tend to need it over time, including specifically rear where I have done very little work on them. Somewhat leery in front as miles on car increase, since as you are thinking about, aligning in a worn suspension with play in it is not great. For D3, when I had to do uppers the second time, it had a very slight shimmy with light braking off a long freeway offramp or something similar. Figured tie rod ends and all the usual other stuff (rotors, tire balance, etc.) but in end it was the upper arms again. I then added the slight shimmy test to the inner tire wear as my indicators for D3 upper arms--plus the creaking and then crunching when really bad. Unbolting ball joint end and moving them around bushing axis remains my Gold standard test, but sounds like you have may have seen enough even in static position to decide to change.

To your original question, I would check Audi OE parts listings for bushings. If they don't have them, less likely there are trustworthy aftermarket. Lemforder also used to show them directly in their catalog for D3. Personally, on front uppers I just use an OE arm and move on, and by 150K the D3 experience would say go to upper arms in front first. Can't find any machine shops in SF Bay Area who do walk in press work either and can't justify a press in my garage w/ everything else--how my old D3 arms with perfectly good ball ends ended up in a box.

RobertISaar

I really have no complaints about what I did with the D3 S8, I wish I would have done it sooner rather than changing out 2 sets of Meyle arms before buying a third and slamming the poly bushings into those before installing them. Meyle lowers had held up great, did those at the same time as the first set of uppers. But everything is "hard" mounted now, it translates road surface extremely well. Lowering the front enough to match the rear fender gap has helped I'm sure.

I'm not sure I want that in the D4 A8 and I'll just keep it OEM feeling. If poly uppers last longer and don't contribute to NVH, I would absolutely do it again, it's preferable compared to the measured guess at arm angle before tightening if done off-car, or lifting the strut until it measures OK and then cranking everything down.

I can't recall the exact details, but I remember seeing an alignment at the dealership on the Carfax not too long before I bought it. Why they did that with whipped bushings, I don't know, any rack tech should have seen it. I think I saw 2022 build dates on the front struts as well, but I could be wrong about that .

I could do new arms, but these feel good otherwise. If I pull them, I just don't want to do it again, that part of D3 ownership has left a.sore spot or two on me.

RobertISaar

4H0407515B

$10 a piece from FCPEuro for Lemforder bushings.A full set of Lemforder upper arms is $340.
strongflex soft poly for 25 each, harder for 28 each. They're showing them as the same application going back a few generations, so maybe the basic geometry is the same?

I think I'll just slam some new Lemforder bushings in and if they fail in a shorter time than I would like, I'll just get new Lemforder arms and put poly bushes into it from day 1, it's worked out pretty well for the Meyle arms on the D3.

RobertISaar

Lemforder bushings showed up, they are dimensionally identical to the D3, the only obvious difference between them is the D4 bushing is fully filled vs the D3 having two small voids that are intended to be installed phased a specific way. The Lemforder/OEM D3 have to some degree larger voids than the Meyle HD D3 bushing I have here to reference. I don't have a way of testing shore hardness but pressing a screwdriver into the rubber, The Meyle D3 bushing feels firmer than the Lemforder D4 bushing.

I'll get these slammed in one of these weekends, it almost looks like I can sneak the arms out without pulling the strut on the D4, that would be nice.

MP4.2+6.0

FWIW, if you have a complete arm or a sturdy vise, you can hold the overall arm or clamp the bushing shell if it's just a loose part. Then take the shaft of a large Phillips screwdriver--like 12" long--and stick it in the center bolt hole. Now flex the bushing rubber---just like happens on the road. Now you can get better sense of rubber flexibility. How I do a close visual on them in the car when worn. Unbolt ball joint end and then move around the center bolt axis without removing arm on bushing side.

Thinking about it big picture, my memory now is those bushings are not there just to absorb vibration and let the arms rotate in only one dimension. They move in that rubber cast area in all three dimensions. Predominately only in the single obvious rotational dimension, but not entirely. Why in turn there are separate front and back arms rather then just the simpler Y type piece with only a single combined ball joint many McPherson strut conceptual design systems use. If you turn the steering left or right--or unbolt the tie rod end and do it by hand at the hub area--that movement becomes more obvious if you look closely.

All in turn why I don't think sold poly makes a lot of sense to maintain factory tuned ride, particularly on D3 where I had a lot of hands on experience. As another trivia item, D3 has a different part number for S8 vs non-S8 bushings and then why Audi has a different part # for the upper arms. Yet, when you look at the Audi D3 S8 bushing side by side with an A8 one, nothing is visually apparent AND same part # is cast into it. I had audiusaparts check into it, and Audi USA reported back they were in fact different but used the same mold casting at the supplier, and hence have same pat # cast in the rubber. If you believe that in turn, it suggests difference was in rubber density or composition. Having used both part numbers in D3 W12, honestly no discernible difference and over time the D3 S8 ones wore out in same sort of 40-70K interval as the D3 A8 ones do. The Lemforder master catalog listings for D3 did not break out that distinction when I last looked maybe 7 years ago, even though they were the Audi supplier for D3 uppers.

RobertISaar

LOLOL, change of plans, getting ready to tear everything apart while getting the trans fluid exchange done twice, I got a much better look at all of the bushings, the lowers are done too. A 16 piece set of strongflex poly is on the way, they worked so well for me on the D3 after a design change that I can't stop considering them for this car too. If I hate it, most of the new Lemforder arms are available via FCPEuro.

Side note, how the D4 is constructed in the subframes compared to the D3 actually looks like a step "backwards"(cheaper/simpler) in terms of design refinement(though some stuff definitely appears more costly at the same time, like the driveshaft coupling). A lot of steel where I was expecting aluminum, the front subframe not using any bushing isolation to attach to the body, and some other small things. I imagine not only is it helping cut costs, it's less problematic/finicky from day 1, it should help more directly connect powertrain to the tires.