So long story short... I had what I, a man of decent mechanical competency, self-diagnosed as a clutch hydraulics failure on my MINI a few weeks back. I replaced both the slave and the master and was having a helluva time getting it bled. I brought it to the dealer, who told me the clutch itself had failed and would need to be replaced. I wasn't entirely sure that was a legit diagnosis, and I certainly wasn't keen on paying them $3200 to do the job, so I brought it to an independent mechanic who came to the same conclusion as the dealer. I concluded that they must be right, and grudgingly agreed to fork over $1600 for the repair. A few days later, they called me with this news:

"We have your transmission and clutch out, and the clutch is definitely screwed up. However, we noticed that the slave cylinder you just replaced is leaking - we sometimes see them go bad as a result of a bad clutch - and will need to be replaced as well."

Legit? I'm not sure just how a slave could go bad because of a failed spring on the pressure plate, and part of me feels like they're just using it as an excuse to cover for work they didn't have to do. I still don't fully believe the clutch on my 5-year-old MINI with only 58K miles would just suddenly blow up.

 

In other make cars we have owned, I have asked for the old parts back when the work order is made up. Fortunately for us in this area, the local MINI dealer in RI and an Independant shop in MA both have excellent reps and Service Advisors/Techs. So never had the need to any more.

Maybe give their SA a call and have him/her go into more detail on that statement.

 

It's very unlikely that your brand new slave went bad right after install all on it's own. Plus if it did and they bought it from a MINI dealer the slave cylinder should have some kind of parts warranty.

 

Ok, I got an update from the mechanics today (after they called to tell me my brand new master cylinder was also bad): They showed me the clutch they had taken out, and explained that the springs on the pressure plate were "much stiffer than they should be". The added resistance of these stiffer springs had thus caused my original hydraulics, AND my brand-new hydraulics, to fail.

So that all seems plausible, in theory. But I'm at a total loss as to why in hell the springs on my pressure plate would become stiffer after 58k? We're talking about a physical change in the molecular structure of the metal here! Seriously?!?

 

all it takes is heat to alter the temper of steel, springs are steel, a slipping clutch produces heat,, but; i have never heard of this happening, which is not to say it's impossible, considering how common glazed flywheels seem to be among us (chewbacca noise when cold) there seems to be a great deal of heat in there, except that the mass of the flywheel and the pressure plate should dissipate that.

possible : absolutely

probable : maybe

but in the end, performance cars have stiffer clutches, if the clutch is bad you need to replace the pressure plate anyway, and if youre changing the clutch anyway see if centerforce offers one.

 

I was figuring on heat being a factor, but the mechanic himself said the clutch disk looked pristine - hardly any wear at all for 58k. So excessive slippage seems an unlikely cause. And I still don't understand why, after almost 2 years of ownership, this would suddenly surface if it were somehow a problem with my driving. And above all else, you'd thing a part specifically designed to operate in a high-friction environment would employ materials resistant to heat.