Do pressure plates wear out?

[xirdneh]

How long can an original equipment pressure plate last?
Is there any way to test them?
Do they ever fail?

[Petros]

yes they do wear out, just like brakes, they are intended to be a replaceable item. I have found they last about 100,000 miles on these and similar lightweight cars, some get far less who do not use their clutch properly. The pressure plate springs get fatigued, they get tiny cracks in the the spring and cover, the plate surface wears and galls and I have seen them fail. That is why it is best to replace both the friction disk and the pressure plate.

The best test is to measure the clamping pressure, but not easy to do. There is a simple "drive" test, it will tell you if it is good, but will not tell you how much life is in it. The test is this: Put the brake on good, and block all 4 tires with wood blocks or bricks, start the car and warm it up, with reves fairly high at about 3000 rpm, you let the clutch out slowly. It should stall the engine fairly quickly, if the engine slowly bogs down than stalls, it is worn, and if you can keep the engine running with the clutch out it is gone. Do not do this very often, or you will have to replace it.

If you are strapped for cash, and your pressure plate has no visible defects (galling on the surface, no cracks or noticeable wear), you can just replace the friction disk and hope the old pressure plate holds up until you have to replace it in the future. I have had cars apart that had a good clutch, but worn, and I did not want to replace it later, so I just replaced the friction disk. If you have the factory pressure plate, it likely will hold up better than an AM clutch. It has been my observation that the factor clutch is more durable than most AM brands. I have also found that a well used factory throw-out bearing will last much longer than a new AM one (most are junk), I always reuse my factory T/O bearing and pilot bearing unless I know they are bad. I have had to pull apart my car less than a year later to replace the "new" t/o or pilot bearing too many times, just to put the old ones back (and than no troubles) after I had replaced all the parts that came in a typical clutch kit.