The HACK said:Sachs makes the OEM clutch discs. ZF makes the 328/330 AND the steptronic transmissions while Getrag makes the 323/325 manual transmission.
I've got ~45,000 miles on my clutch, about 90% highway driving although for 6+ month it was spent in heavy L.A. rush hour traffic. I am moderately aggressive, with the average shiftpoint between 3,500 RPM and 4,000 RPM, and on average take my car all the way up to redline once a week. I have done several casual clutch dumps at 3,000 RPM with minimum wheel spin. I've done one track school, and one Malibu Canyon run.
I think if I take my clutch disc apart now, I'd guess I would still have over 75% of the pressure plate left, if not more. The clutch feels as solid as the day I picked up the car.
Mystikal said:If the replacement of a clutch wasn't so labour-intensive, I'd love to put in one with a much higher clamping force that could take some serious abuse. Something that would live through multiple hard launches daily. Then again, I think worrying about the clutch life keeps my acceleration levels in check.
A common failure item on BMW clutchs is not the clutch disc itself but the something-something bearing (sorry, early morning, no coffee, and a very, very sore neck). Also, the spring that pushes apart the pressure plate will wear quicker, if you tend to keep your foot clutched in while stopped at a light.JuanCarlos said:
Somebody mentioned clutches sometimes failing without showing much wear. That's probably due to the springs on the pressure plate losing strenght (and it makes sense, right?). It'd be nice to know how long they should last, since it seems not to be related to mileage. But if that's the case, how about valve springs?