looking for some advice, when I’m putting around in a parking lot or stuck in stop and go traffic in ‘S’ mode, the car (2007 S6 V10) downshifts from 2nd to 1st as I’m rolling, I step on the accelerator it revs and then slams into gear typically 2-3k rpms when it engages. I’ve been able to duplicate it in manual mode, rolling ~5mph in 2nd, downshift and then accelerate, once again 2-3k and Bam it engages, rips my head off and starts to go. I’ve tried several OBD2 scanning tools and can’t find any codes in ECUs for either motor or trans. the rest of the shifts seem pretty soft, in manual mode the shifts seem better than in ‘D’. Shops have so far focused on getting rid of my misfires, they have been resolved, so now just tranny issues.
Welcome to the site. What your talking about many on here call it the ZF surge or lurch. It is common to the ZF transmission and you see it in BMW Audi and a few other cars the Zf6hp came in.
There are a few options that some say work. You can change your fluid and filter as that helps some. If your local to JHM they have a TCU tune that fixes the issue in the programing or you can drive around it.
My suggestion would be start with the fluid and filter. fluid you can use redline. Its just as good as the oem stuff if not better in some peoples opinion and its cheaper.
thanks for the welcome and response. I’ve read that most owners say its a bad idea to change trans fluid unless absolutely necessary, I’ll look into JHM. thanks again.
IMHO most maintenance minded owners change there transmission fluid. I too have read owners saying they think its bad but its only bad if you have over 100k and you have never changed it.
The notion behind it being bad is that some are stuck in the 1980s thinking frame of mind. with current new tech and updated parts in the 6hp changing the fluid is something that you can do at any point in time (within reason). Again if this was a 1994 automatic transmission I would say sure you need to be careful on changing the transmission fluid because its thicker now due to clutch material being in the transmission fluid and on the older transmissions you could run into slippage if you put in new fluid if the clutch packs were too far worn down.
BUT. On the 6hp its computer controlled so the old myths and old issues are not going to apply here on changing fluid. As a matter of fact almost all of the guys who do change their transmission fluid say how the transmission shifts smoother and faster. Many have claimed this completely eliminated there issues.
IF you think about it. If you have a clogged transmission filter or thicker fluid than needed there will be a delay in the transmissions ability to pump fluid to properly down shift and apply clutch pressure. The newer fresher transmission fluid helps keep heat in check… has fresh antiware properities and obviously is able to be pumped faster and flow faster. The concern of clutch slippage isn’t going to be an issue due to the fact that the TCU computer would simply apply more clutch clamp pressure if the transmission was slipping.
In all the Audi 6hp transmission flushes I have done or read about being done on this forum. Not one of them has had post flush issues. Almost all of them have reported much better driveability and the rest say they can’t tell a difference but never a bad report.
So I would be cautious of the owners who say its a bad idea as you don’t know if they are just passing on old way thinking or if there is actually something to it. IMHO I have never seen anything but good coming out of the transmission flush and fill.
In the end do what works best for you. Just wanted to pass on my first hand experience.
thanks for the response, I bought the car with 96k, now has 102k. not sure what has been done in the past. so far I’ve had over 15k in warranty work done on it, Intake manifold, plugs, coils, injectors, valve cover gaskets, carbon clean. not sure how much more its going to take before I can feel like its good to go for a while. sounds like a trans flush and filter change are next on my list.
I would suggest you do. Obviously check the TCU for codes before you venture into the flush.
One thing to note. There are many many very smart technical guys on this site. Most of the technical guys read and some post here. We have all left the other sites due to drama and not wanting to be part of or deal with the drama.
There is nothing wrong with opinions but we like to help make sure to offer the facts best we know. There is a lot of stuff that gets put out there like you mentioned guys talking about not doing this or not doing that because they have head this or that over the years. On AR we usually can back what we post on facts or experience. So never feel bad about asking questions.
What he said. I lurked on a few boards before coming here. AR is the only one I’ll trust.
FYI for transfluid, after extensive research, Mercon SP is the exact same stuff. both ZF lifeguard and Mercon SP are made for 6HP trans and made by shell spiralax in texas. I have 10k miles on the mercon SP and trans feels fine.
What warranty out there actually covers all of that stuff on our cars? Please refer lol
Does it do it in normal mode (D), or only in sport mode (S)?
Most of our S6’s experience this same “ZF Lurch” when driving in S mode. It happens when you hit the throttle while the car is downshifting from 2nd to 1st, usually around 2-3mph.
Apart from figuring out what the cause of it is (which I don’t think anyone has, yet), my solutions have been either:
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Don’t do “rolling stops” in S mode. Once the car slows down to 2-3mph, just bring it to a complete halt before hitting the throttle again.
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Don’t drive in S mode during stop-and-go driving.
FYI, I got the JHM TCU tune, and while the tune is excellent in many regards, the ZF lurch is still there (though it doesn’t seem to happen as often, perhaps because of the tune, or maybe just from changing my driving habits). I think it’s a hardware issue, not a software issue.
Interestingly, my boss just picked up a 2011 Maserati, whcich has the 2wd version of the same ZF 6HP transmission, and his does not have the same lurch. I drove it around this morning and attempted to get it to lurch from 2nd to 1st gear, couldn’t do it. So it might be specific to the 4wd version.
Funny side note, he was mad when he found out that my 2007 Audi sedan is faster ;D
…interesting. and lol…
I want the TCU tune but have to drive up to MI to get it. Is it worth the 18-20 hour round trip and the small price of the tune? I’m thinking that it probably is, but figured I’d ask lol
I got the TCU and ECU tune, plus a carbon clean and basically every other thing listed in my signature, done all at the same time, so unfortunately it’s really hard for me to say exactly what the TCU tune by itself would do. Hopefully someone here has gotten just the TCU tune by itself and can say what kind of improvement it would do by itself.
I do know it’s worth getting the ECU tune done at the same time, though, if you haven’t already. I believe it’s the same process, so you’d essentially only be paying for labor for one of them.
Cool. Yeah I have the way tune but apparently you have to be on site for the TCU tune. I’ll probably end up going anyway. Just trying to decide if doing a track weekend is more important to me than the tune, since they’d both cost me about the same
I have an S4 4.2 but I do have the TCU tune and since Im local to the metro detroit area I have had a few revisions of it up to what is current on what would be both the 4.2 and 5.2 6hp transmission tune.
The tune can only be done in a few spots due to the fact that almost no one can tune the 6hp transmissions and almost no one does. So the flash ability costs a lot of money. JHM can flash your ecu but the TCU is a harder ball game and they have worked to make a flash tool for it. The tool is expensive and why they only can do it in JHM CA or JHM Mi.
Results wise. you will see and feel a difference. Lower trans temps from less slipping of the clutches. Faster pump speeds so a stronger clamp force for better acceleration. Better low end launch ability slightly raised shifting points to take out the ocward OEM shift points. feel wise you feel a slight bump when the car shifts and its a crisp quick bump so its not bother some. With low low throttle input you can see the car complete the shift faster but you dont feel it. WOT the car is much more stable and the shifting results are closer to dsg shifts where they are very quick and strong.
Overall I enjoy the car more now with the TCU tune. It was like getting JHM tuned all over again and there was a big jump in acceleration fun and smiles per mile when I did the JHM ecu tune the TCU tune is on that same level
I may be making the road trip 5o get this tune. Sounds like it’s worth the $700 and the long road trip
USAA is the company I bought my extended warranty thru. it did cost me my dealership tho. long story but for the first year I had the car it was in the shop for 60% of it. was driving a loaner car, can’t complain new audi cars are nice. but at the end, they said they will no longer accept USAA warranty work, told me to take my business elsewhere, I can’t blame them, they spent more on my loaner than what they got in repairs due to the run-around they were getting. several requests for some 3rd party inspector to verify repairs were required,etc…
anyway I do appreciate all the responses.
back to the subject of my trans, the JOLT that I get happens in both ‘S’ mode and manual when I down shift from 2nd to 1st while rolling and then try to accelerate. not sure I’ll just avoid that spot while driving. I was worried that its a sign that the trans is going to give it up soon, but seems that its just a “feature” of the 6HP, nice.
overall I have to say I like driving the S6, but not sure I’ll ever buy another AUDI. the schematics that we have access to from eBahn sucks ass. youtube has limited content for us. these are so rare that its hard to find people that have experience on them to help troubleshoot, modify etc. I’m not rich enough to afford owning this thing long term! meanwhile I’ll drive it like I stole it.
Unfortunately the 5.2 is probably the least documented “modern” engine produced by Audi because as you alluded to, rich people would just take them to the dealer and let them do their thing, leaving the rest of us in the dark. Granted even since I have taken ownership of my S6 a little more than a year ago I’ve been noticing more and more threads/resources popping up helping us document some of the repairs that typically went overlooked.
I wouldn’t give up on Audi afterwards. The newer 3.0Ts and the 2.0Ts have a much larger enthusiast following, things are significantly easier to work on due to there being a little more space, and the prices of parts are a little more reasonable.
In retrospect, I probably would have gone with an A6 with the 3.0. But I will continue to drive the S6 around for the time being. This car certainly flies under the radar, and I’m almost certain I’ve encountered a few guys on the road at night who thought they were fooling around with an S4 only to realize there was almost an extra 100hp unaccounted for ;D
I think the 5.2 S6 and S8 motors are getting attention now after a long time and when you condsider that JHM has been able to turn a once 14 second 1/4 mile car into a 12 second 1/4 mile car with acceleration that you see in a RS4 I would say performance wise there has been a big jump with the addition of JHM and the supporting mods there.
As for the maintentance side. Its still hard. You can see so many little things causing misfires but I have to say in just the past few years alone we are really getting a hold on what issues are top issues and what formula can really get you best results in both maintenance and performance. The reality of it is once you really get all the maintenance work done you should have a really solid car.