dvs_dave

My 04 A8L 4.2 has 77k miles on the clock, relatively few for its age.

Anyway, for the 10k miles I've had it, I always felt the gearbox never shifted quite as smoothly as I thought it should, particularly when cold. Nothing major, but shifts were sometimes slightly rough and slurred, with the occasional noticeable bump coming to a stop as it shifted from 2nd to 1st. Also when setting off briskly it would sometimes feel as though it slipped slightly, or did a change from 2nd to 1st. It never developed the infamous "hoot" though.

So after lots of research (https://www.audiworld.com/forums/a8-...2676/|see here) I decided to do an ATF and filter change and put my money where my mouth is and chose to use Redline D6 ATF.

Procedure went well, the old fluid was not particularly dirty, and the pan and filter were also fairly clean considering 11 years and 77k miles. New filter and Redline D6 ATF in (2 drain/fills, approx 10 quarts, to get 80-90% of fluid changed), topped off to the right level, no error codes or anything so was good to go for a test drive.

I wasn't expecting there to be much noticeable difference if any, but either way peace of mind with fresh fluid.

Well, what a difference! The shifts are so much smoother, quicker and totally seamless! I was really surprised at how much smoother an already smooth gearbox had become. Other than engine revs, gear changes are now imperceptible and smooth as silk. It also shifted more quickly too. Tip Tronic mode it popped through the gears a lot slicker and quicker too. No 2nd to 1st thumps coming to a stop either.

Will see how things go long term, but given the greatly improved performance over the old factory fill fluid I'm not anticipating any issues. Hopefully my experience will help others on the fence with going ahead with this as it's patently worth it!

MP4.2+6.0

Good report.

Your pan report isn't too much different than mine, at least relative to earlier era Audi trannies I have done. Per various other postings I've done, I think the discontinuance of lead for lubricating characteristics has probably resulted in less of the clingy mucky stuff on surfaces and in the pan than in older units.

BTW, single fill after pan pull, or multiple drain cycles? Also, did you do an adaptation, or just drive it with TCM learning as it was?

dvs_dave

I did a secondary drain and fill. I was prepared to do an adaption but as it was shifting perfectly right away, there was no need to.

The.aviator2

That's very good to hear.

Speaking of that, and since I'm fairly new to my S8, I noticed a delay in engagement after I put it in D- or R. Also, when starting to accelerate, the car tend to jump off the line rather than drive smoothly.

Do I need an ATF change too?

MP4.2+6.0

Thanks. Agreed on no adaptation if feel/shifting is already solid.

The.aviator2

I just came back from the dealership here, and he also told me that ATF does not get replaced, ever.

This seems to be the most controversial topic in this board. Between the manufacturer's recommendation and what people have experienced after replacing it, falls the real question mark!

There's a saying in Arabic that says " ask an experimenter rather than asking a doctor!". Myabe that's what I ought to do.

SaltyIrishman

I don't have the delay issue, but that throttle response is just the way the S8 transmission and motor works. You WILL spill drinks, snap your own neck back and have stuff flying all over the car, especially if you try to pull out in front of someone "quickly" on the road from a stop.

It's an acquired skill to smoothly modulate the throttle in this car

uberwgn

Aviator, it seems that ZF has created a magical fluid that defies the basics of chemistry and oxidation! Especially in operating conditions with high ambient temperatures At least that's what they (the dealer, Audi and ZF) would have you believe.


The dealer is telling you what the manufacturer goes by. The transmission does not need to be serviced unless it's operated under severe duty conditions and it will last a "lifetime". Audi/ZF have not been able to define "lifetime".


If you intend to keep the car beyond 150k kms or operate it under severe conditions, you may consider maintaining it.

Aceler8

Our 2006 A8 occasionally shifts hard moving from 1st to 2nd, but otherwise its silky smooth.

Our former 2000 A6 never had a fluid change and we ramped up 10 years and 220k miles.

allenst

well congrats on your success !

I'm really curious as to why you got such noticeable positive changes.
just simply a modern oil and a new filter ?
many have had no drive change after doing these procedures so it's great you did it a positive way.
after mulling for 2 weeks, and having the same issues you HAD, I will do the same this weekend.