Urgent feedback needed - Failed clutch slave cylinder

[bguild]

Hi All,

I had clutch pedal go to floor at a coffee shop of all places. 90k on a 2011 B8 S4. No clutch activation possible at this time. Dealership diagnosis confirms failed Clutch Slave Cylinder and they want to replace at a cost of $500.

But they are also saying they should "drop transmission" as there might be contamination from broken parts.

Here is where I need help as I dont want to pay $2K to have them drop tranny.

1) Is the design and attachment of the slave cylinder fully external to the tranny?

2) Is it possible for a broken slave cylinder to contaminate tranny or clutch given the design?

3) If I chose to not have the tranny dropped/inspected what risks am I taking? Is that a risk of future clutch failure, tranny failure or both?

As always I am just trying to confirm if the dealership is pulling my chain, as from what I can tell this entire part is external to the housing and I cant ascertain if any associated parts are internal.

Thanks for any help.

Brian

[Jay@JXB]

Yes, no, and don’t let them do it.

Did you have the push to start issue leading up to this? That usually causes slave failure.

Take it to a smaller shop for replacement. It’s an hour job tops.

Check out my extended slave if you’re having push to start problems or want to prevent them in the future:

https://www.jxbperformance.com/products/extended-slave-cylinder


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[Jay@JXB]

For the 2nd question, the only way there’s contamination is if you can’t find all the pieces of the slave cylinder. They generally just crack, not explode so you should be fine. Even if a piece of plastic made it into the bell housing, it’s just in the clutch area and will sit at the bottom and do no harm. I had a broken bolt flying around in there for a while and wasn’t a big deal.


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[Ray Khan]

Agree with both jbullin2 on both points. Had a local Indy shop (not even Audi or German specialty shop) replace my slave cylinder a while ago. Mine hadn't failed, but I was having an issue after hard shifts where the clutch pedal resistance would seem to get very light and then come back after I pumped it a couple of times. I had them throw in the ECS hardline while they did it so I could remove the clutch delay valve and rubber line.

[bguild]

Super helpful guys. They say a piece of it broke off. I am going to try to get the dealership to show me the unit they removed. So as to ascertain where the break occurred.

Not sure if they will do it. Also not sure if they will agree to just do the slave and have me "accept the risk". I'll have an update later today.