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I have a Subaru STI 2009 with 180k kilometers on it a very hard clutch, closer to a truck than a usual car. It works fine and has been that way for at least the two years I've had the car but it is so hard that I wore through two master cylinders within the last year and if I remember correctly the Western Star 4900 I tried last year had a slightly softer clutch.

I also tried another, more recent, STI and the clutch was hard for a normal car but nothing like mine.

Now after watching a few clutch videos I wonder if simply opening up the clutch and greasing the throwout bearing axle and other sliding parts could solve, or at least help with my issue?

There is no rattling noise when I use the clutch, and it works great apart from the fact that is is pretty much impossible to do a clean start without any vibration. It feels somewhere in between that other STI clutch I've tried and a race clutch I tried a few years back on a Jetta VR6. The race clutch had more vibration but was softer than my clutch.

A possibility would be that a previous owner modified the pressure plate for a heavier one but I don't know how I could verify that other than opening it up.

Johnride
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3 Answers3

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Don't try greasing anything inside the bell housing. Grease will get thrown onto the friction plate and cause you problems.

If the pressure plate is faulty or a previous owner had a heavier plate fitted then the only cure is to change the plate for a "normal" one.

Solar Mike
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It is possible that you have a warped pressure plate which prevents smooth engagement of the driven plate.

It is also possible that your driven plate is exceptionally hard, or lacks all the springs in it that it was designed to have. (That is it is not as soft as it should be.)

Those are just theories, and if the problem bothers you enough, you get to decide whether you should take it to a transmission shop for diagnostics.

I do not understand why you went through two master cylinders with this problem. Is it that there is lots of vibration at clutch engagement?

Unfortunately, with clutches, other than linkages and engagement cylinders, most of the guts are inside the bell housing. If you were to open it up to "lubricate" things, I would rather open it up to inspect the components. Once you have that kind of labor, simply replacing the components may not be that much more, and will rule out the two plates which are likely causing your problems.

To be sure, is the clutch hard upon engagement, or heard to release? If hard to release, that could be a different set of issues which I have not specifically addressed here.

mongo
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I would take a look at the slave cylinder. If you are wearing out master cylinders something is not right.

It may be the slave cylinder has worn away a pocket in the release lever. This is supposed to be lubricated with special grease. It's not easy to get to, but it is external to the transmission.

Check the interface to see if there is rust or abnormal wear on the release lever.

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SteveRacer
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