A different kind of clutch problem?

[grmnshorthair]

Gents, this is my first post so please bare with me. I am the proud owner of a 2010 R8 V8 MT6. I bought it used 2 years ago with 2500 miles on it and have since added another 32000 miles. About 3-4 weeks ago I started experiencing a problem with my clutch and I am wondering if any others have experienced the same problem. It has happened at least a half a dozen times. Usually it occurs when I have been running on the freeway for a few miles at freeway speeds (75-80 mph) and start to exit the freeway. When I depress the clutch to down shift, the clutch peddle will go all the way down to the floor before it disengages the clutch. It shifts normally with the exception the engage/disengage point has moved about 1-1/2". The clutch is not slipping. Within a few shifts, things seem to go back to normal and the problem may not duplicate itself again for days. To me, it seems more mechanical than hydraulic. Audi basicly told me to drive it until something breaks, they couldn't duplicate the problem. Any suggestions.

[desperado]

Sounds like it IS a hydraulic symptom. I say this because the multiple-shift-thing curing it temporarily sounds like you are "pumping up" the clutch. Could be a low brake fluid reservoir, a leak in the clutch hydraulic system or even a loose clutch bleeder, or might be caused by the clutch slave cylinder (inside the bell housing) going bad.

This problem is going to strand you one day, so I wouldn't let the dealer get away with an "I don't know" answer.

[grmnshorthair]

Thanks for the input Desperado. I mentioned to the Audi mechanic originally that I thought it might be a seal lip that is flipping over every now and again as there was no obvious external leakage. But that didn't really seem to plausible. Then I started thinging "mechanical". I realize it's difficult to diagnoise a problem that you can't duplicate. I don't know if the mechanic checked fluid levels or not.

I am due in for my 35,000 mile service as we speak and I will mention the problem to them again. Probably after the first of the year. I'm not sure what all is covered in that service. I would think that checking fluid levels would be. I am assuming access to the clutch master cylinder reservoir is behind the clutch peddle with access through the trunk? Or is it on the inside of the firewall? If it's not to difficult, I will pull the pannels off and see that there is to see. Again, thanks for the input. I'll let you know what I find.

Frank

[desperado]

IIRC the clutch shares the brake fluid reservoir. So access is under the plastic panels surrounding the trunk (under the front hood).

[grmnshorthair]

Before I had a change to decide when I was going to take the car into the dealer's for service, it made up my mind for me. At the Tour D' Orange on Jan 1st, the clutch finally decided to act up and stay that way so I was able to get it into the dealers on the 2nd while it was still acting up.

A very long story short, the mechanic found reservoir fluid levels were normal and no external hydraulic leaks were visable. He bled the hydraulic system 3 times plus they did the 35K service. We went for a ride this morning and the clutch seems to be working fine. The engagement point is a little higher than normal, but not by much. Apparently there was some air in there somewhere but for now it looks fine. No reason for the air in the system or why it didn't bleed itself off.

Per the mechanic, it looks like I might be due for a new clutch soon too. Desperado, I saw the picture you posted re:clutch plates ID. What is the deciding factor as to when to change the clutch or not on the MT6? Assuming it's not slipping. I know it's probably a loaded question but not knowing the clutch plate thickness new, it's hard to know how much wear there is. My guess is my plates are almost down to about 1/16", maybe 3/32" thick. Not a lot left. I have read in the forum that the V10 clutch pack kit might be a good replacement for the V8. Any thoughts or comments on that?

I want to thank you for your input Desperado. I know your not to far away from where I live. Maybe we will get together one of these days and you'll let me buy you a cold one. Thanks.

[desperado]

I don't know the minimum thickness of the clutch plates, the point where the clutch will start slipping. The plates do seem pretty thin to start with, so I'm guessing the amount of wear would seem pretty small! Perhaps one of the clutch vendors on this forum with direct knowledge can shed some light on this for us?

I never noticed any difference in driveability between the two different clutches in my V8, but then I'd changed the engine (added FI) at the same time I changed the clutch. Right now the car has been converted back to NA, but honestly it has been so long that I don't remember the clutch feel prior.

Anyway, IMHO the upgrade shouldn't be warranted unless you have increased the engine power.

If you'd like to visit just PM me and we can find a time to get together.

[KfabR8]

The clutch master cylinder has gone out. It will be an intermittent problem at first and then become more and more often. This happened on my 08 and on that p.o.s. 09 Twin Turdbo that I owned. Easy fix - have the dealer replace the master cylinder. It's a fairly quick job to do.

[grmnshorthair]

The clutch master cylinder has gone out. It will be an intermittent problem at first and then become more and more often. This happened on my 08 and on that p.o.s. 09 Twin Turdbo that I owned. Easy fix - have the dealer replace the master cylinder. It's a fairly quick job to do.

KfabR8, funny you should mention that. I picked up the car late Monday and have put probably 120 miles on the car since with moderate driving. Tonight was the first time I felt the need for speed. Getting on the freeway I went through moderate acceleration in first gear, shifting about 5-6000. Second and most of third gear with an agressive throttle, shifting from second about 7500. When I shifted into forth at about 80, the clutch peddle was back down, almost on the floor, just as with my original complaint. So it looks like the dealer is going to get a call in the morning. I will also call Audi's Customer Experience Center and let them know what's going on.

I'd like to thank you guys again for your input, your experience and expertise. It's nice to talk to someone who has been there, done that. Someone who's not trying to piss on my head and tell me it's raining. For that again, I thank you. Saga to continue.

[grmnshorthair]

OK, just to keep you in the loop... Finally after receiving parts from across the pond, a new hyd. hose and new clutch master cylinder were installed. I as still getting used to the new "feel" of the clutch peddle so I am not drawing any final conclusions yet. I'll put another few hundred miles on the car and then I'll update the thread. I certainly hope this takes care of the problem. I'll let you know.

[grmnshorthair]

Well, long story short, as my car seemed to be running ok, I decided to take a road trip. After driving 260 miles, I turned off I-15 into Las Vegas and went to down shift. I had no clutch and had to force it out of gear. I got towed to a local Audi dealer where they found I had a leaking clutch slave cylinder. Parts were ordered, repairs were made and 6 days later I was back on the road.

With almost 36,000 miles on the car and while repairs were being made, I thought it might be a good idea to replace the clutch pack. Especially as Audi was picking up the labor. It had previously been suggested by an Audi dealer but when I asked why, he couldn't really answer the question. The clutch had been working fine. I had asked the mechanic to get me some new clutch dics thickness readings so I could compair them to my old clutch. Unfortunately I didn't get what I was looking for. But it seems there was so little wear on my old clutch discs that had I know before the repairs, I would never have replace the clutch pack. At least I have something to reinstall if I ever need to.

I would attach some pictures but don't know how. Sorry. Thanks guys for the help. Let's hope this does it. Frank