mc-io

Hello all,

I have a 2017 A4 Premium Plus Quattro with about 45k miles. I bought it CPO with 30k miles about 1.5 years ago.

Ever since purchasing I've experienced some erratic transmission behavior:

1. When driving at low speeds, I notice a small "bump" (or maybe could be described as a very slight lurch) when I ease off the accelerator. Maybe I'm feeling the clutch disengaging? It does this when cold or warmed up, and I notice it most at low speeds, like when navigating a parking lot.
2. Slightly hard 1-2 shift when cold - my old Honda did this too but had 4-5x the mileage
3. If I slow down and reapply the throttle without stopping completely (like rolling through a stop sign for example), when the clutch re-engages it is a bit harsh/hard/pronounced. It catches immediately but it's a bit of a jolt. I wouldn't expect torque converter levels of smoothness but it seems harsh for even a DSG.
4. Perhaps the biggest problem of all: when I take my foot off the gas, for example during a turn, and reapply the gas out of the turn, it will occasionally shudder/sputter for a second or two like it's trying to "catch" and reapply throttle - almost like a kid driving a manual for the first time. This doesn't happen very often but is unsettling when it does.

I'm not 100% sure if these are issues with the transmission itself, the flywheel, transmission or engine mounts, differential, drive shaft, etc. All of my issues occur at relatively low speeds. Under full throttle the shifts are extremely quick and smooth. That's great and all, but I can't always drive the car at 100%.

Something worth noting - when I brought my car into the dealer for unrelated warranty work this past year, I was talking to the service advisor about the car's service history prior to my ownership. He noticed the transmission was replaced under warranty at around 20,000 miles. This was prior to my ownership and not at this dealer, so the SA had no information as to why it was replaced. I worry that this may be the root of my problems - either the replacement is having issues, or the dealership didn't do a great job replacing it, or missed a step like resetting the adaptations or something. It's also worth noting the 2020-21 loaners I've driven seemed to have much smoother transmissions.

The A4 does require transmission fluid changes every 40,000 miles. I am at 45k and haven't had it done, since the transmission was replaced at 20k, so the transmission should only have 25k miles on it. Unsure if a fluid change would make a difference or if there are underlying issues. I was planning to get it done sometime between 50-60k miles.

I really appreciate any insight provided from the community. I know dual clutches can be finicky at times but the couple A4 loaners I've driven didn't seem to have the same issues. I'm debating if I bring the car into the dealer as the CPO extended warranty expires in March 2022. I have a feeling they will say it's working as expected - which if they do I'm afraid I might have to part ways with the car earlier than expected. Unfortunate since I haven't had any real issues apart from this; I love pretty much everything else about the car. At least it's worth more than I paid in this crazy market.

Thank you again for your help!

Alexandru.k_24

I am also experiencing points 1, 2 and 3. But at a 8 speed transmission, wich in fact is a ZF 8HP transmission. I have experienced those symptoms at every car with 8HP transmissions after a while. (BMW, Audi and a Jaguar). Maybe the tune of the transmission differ from brand to brand but all of those had the same behaviour. Even after a fluid change or mechatronic replacement. I have sold one car because of this reason ). When i bought it the transmission was shifting just perfect, but after a while that behaviour encounter. I have replaced the transmission fluid and after a while the mechatronics. Nothing seemed to change the behaviour of the transmission. So, i sold the car. After a year or so...i drove that car again and i was expecting the same behaviour. But, surprisingly...the transmission ran beautifuly with no flaws :| So, i'm thinking that is our fault with our driving habbits and transmission adaptation.

bdh1119

My ‘18 A4 exhibits the same trans behavior, which I chalk up to its design. The most abrupt shifts happen when it’s cold, but after the trans is up to temperature, it’s generally smoother but still lags and bumps at times. Popping it into sport mode makes it much more responsive and usually more predictable.

142 guy

How does the car shift in manual mode, do you get lurching or other erratic behaviour when you manually initiate shifts?

If it is still under the extended warranty, the very first thing I would do is to register a complaint with your Audi service department and see where it goes from there. No point in you looking for solutions on your own if Audi agrees that there is a problem and attempts to resolve it. If Audi determines that there is not a problem (that they are prepared to address) at least you have a service record and perhaps some basis for compensation if the transmission subsequently fails out of warranty.

If the original transmission was replaced at 20,000 miles, perhaps the previous owner had a driving style that contributed to an early death. Since the previous owner had the car for 10,000 miles with the new transmission before you acquired it that driver may have accelerated issues for the new transmission. The service interval on the transmission is for the fluid in the mechatronics / clutch system as opposed to the actual 'box full of gears'. The mechatronics fluid cools the clutches so it is the fluid that probably get the abuse with an aggressive driving style. Since the previous owner had the car for 10,000 miles after the transmission change, an accelerated mechatronics fluid change might not be a bad thing. If the fluid change does not fix the problem, at least you have eliminated it as a cause and its likely a lower cost relative to the other repair options.

I seem to recall comments that in the auto mode the DC transmission has an adaptive controller. The controller may have learned some aberrant behaviour which is contributing to your drive issues. I admit that adaptive feature is 'internet wisdom', since I don't recall any info in the owners manual or the service manual on that feature. You might want to explore whether there is an adaptive feature and how it is reset to the factory start mode, although I would expect that your Audi service department might try that as a first fix if that feature really exists. Doesn't hurt to ask.

PghRich

Most of these are familiar, and likely characteristics of the DSG. It's always hard to tell the degree to which you are experiencing these symptoms through forum posts.

Dual clutch has likely pre-selected first as you slow in second, and when you accelerate, it needs to swap for third.

4 may be the same - lift throttle signals an intent to slow.

When a dual-clutch correctly prepares for the next shift, which is most of the time, it is extremely smooth and quick. When it doesn't, it can be a bit of a mess.

1killera4

DITTO.

dmski

Reviving an older thread, but have others found a possible solution to this? Noticing more harder shifts in low speed scenarios and understand this can be the nature of the DSG beast, however some are a bit more pronounced and lead me to believe engine mounts could be a culprit, otherwise it's shift calibration/adaptations that I'm wondering about. I'm at 46k 2017 A4 B9, original mounts. Possibly a solution i've considered is a transmission mouint insert but I'd like to figure out the original issue if possible.

142 guy

46,000 miles? If so, have you had the mechatronics flushed yet? If not, the scheduled flush in the Audi service schedule for the mechatronics is every 40,000 miles. If you think you have shifting issues I would have that flush carried out first to see if that resolves the problem with hard shifts rather than looking for other problems. Carrying out the scheduled flushing of the mechatronics will never be a bad thing, even if it does not resolve whatever issues you might be experiencing.

dmski

ah should have clarified, just did the DSG fluid change 6k miles ago as well so this is just after having done that. Still rather rough shifts. I did have a dealer do this so my cynical side of me thinks it could be a scenario where they in fact did not do it but I doubt this as well.

142 guy

Since you have already picked off the low hanging fruit, two additional things to consider, a transmission reset and firmware version. There is a process where you can reset the transmission controller to the original factory baseline which may help if the TCU has learned some bad behaviour. I have never had to deal with this so cannot advise on the reset process. Between 2017 - 2018 there are anecdotal statements that there were firmware changes to the TCU firmware specifically to address rough shifting. You can find TSBs covering the firmware changes for some models; but, I was not able to find a TSB covering the 2017 A4. I you had VCDS I think you should be able to find the firmware version for your TCU and then see if there is a more recent version.

If the roughness you experience has always been there then the firmware update (if it exists) might help. If the roughness has emerged over time then that is not a firmware issue; but, doing a reset to the factory baseline might help.