Sjorge3442

Was the 5 min of driving done on a cold car? I wonder if the Ultra system doesn't stabilize until transmission temps are fully up to operating temps. Either way, if you still have those noises occurring, it needs to go back to the dealer

Bobert

So my car is a 2018 and I'm at 85 k miles now. I had the ultra awd an diff fluids serviced around 70k miles and everything was good till recently when in 3rd gear I was getting pulsing or rythmic vibrations under light throttle 50 percent of the time. Now the vibrations are twice as bad 100 percent of the time in 2nd,3rd,4th,5th under almost any throttle and they replaced the awd unit with the controll module from what I saw looking at it yesterday filming. I'm thinking software needs to refreshed or possibly adaption done properly as 142 guy said. But I do not have e any dtc's

So I had drove the car home from work then took 30 mins to figure out how to mount the go pro... so it was up to temp but mabye still a little cold.

I did a little more filming and what i saw was no matter what when coming to a stop or taking off slow and accelerating, the drive shaft was spinning. Only when cruising at a constant speed did the drive shaft stop spinning for a little

Here is a YouTube video I uploaded of the longest I saw the drive shaft stop spinning

Sjorge3442

Here is a link to a document from Audi that explains the AWD Ultra a bit more. Per the documentation here, (Starts at page 26) it shows that the car is probably NOT in FWD mode more often than most people would claim so I wouldn't get too caught up on the driveshaft not disengaging more. Id assume you'd see it disengage mostly on smooth, straight, flat highways with cruise control enabled.

You could probably test turning off ESC to see how that impacts things too.

Bobert

Did any of you guys feel ryrhmic/ pulsing vibration under acceleration before you replaced your awd clutch fluid. My car has been at the dealer 2 weeks now. They are now saying the transmission is bad. They supposedly worked with audi tech line. I still don't understand how I felt all the same symptoms as you guys but awd replacement only made it 2x worse.

Sjorge3442

I dont recall any pulsing when I was having my issues originally. Is it pulsing like a clutch slip pulse? Im confused as to how the transmission could produce a pulsing feeling. Id think more along the lines of clutch/flywheel or something in the ultra clutch for that sort of feeling.

Bobert

I was thinking it was the clutch and told the shop foreman that when i went for a 10 min test drive with him... he said that's not it because theres no indication of clutch slip and vibration disappeares when going full throttle. I agree with you, dosent make sence how it could be the transmission. I'm still thinking they diddent program the awd unit properly