It's obvious that these are hydraulic clutches (as opposed to cable-actuated). Our Focus is an auto trans, but my Saab is a manual with a hydraulic clutch. The only info I don't know about the Focus' setup is if the hydraulic fluid is shared between the brake system & the clutch system, or if they use two separate reservoirs. Can you answer that for me?
Transmission oil should have absolutely nothing to do with this problem.
My Saab uses a shared reservoir. Of course, the standard maintenance interval for brake fluid has always been "replace every 2 yrs or 30k mi, whichever comes first." This is because brake fluid absorbs moisture from the atmosphere, & that water will eventually corrode the metal lines & caliper parts. With a shared reservoir, you should flush the fluid out of the clutch line at the same time that you do the brakes.
And that's as far as most people go (if they even think of it). However, I've learned over the years that the clutch really needs flushing more frequently in order to maintain proper feel & function. This is because the seals & pistons of the clutch system travel so much more than those of the brake system, & so they generate much more wear & debris that needs to be cleaned out. Because of this, I do my clutch at 1 yr intervals.
If your hydraulic fluid is of unknown age, flush both the brakes & the clutch systems. The fluid's probably pretty nasty. Drive it for a week or two, then flush just the clutch system again. The fluid will still look like crap, but it should be better than the first flush. At that point, you're good for another year. When next year rolls around, just do the clutch system again.
I forgot to say, these symptoms (indicating old fluid & deposit buildup) typically show up when the weather turns colder. Seals aren't as flexible as when it's warm out, so the hydraulics function much less efficiently & these symptoms start showing up. I just went thru this on my Saab, here in Northern Colorado, with the clutch engaging almost at the firewall. After performing the flush/drive/flush sequence I've been following for the past decade, my clutch engagement has now returned to the end of the pedal travel where it should be.
"Help, Mr. Wiza-a-ard!!"
Last edited by Eiron; 11-28-2012 at 04:29 PM.
Reason: Additional info