What is a reasonable life span, in miles, on the clutch in my Boxster? Also, what signals would be coming from a failing clutch?

The vehicle has never been tracked, and I drive like an old lady mostly on Interstate roads.

Thanks for your consideration,
Brad

 

It varys a decent amount. Most people replace clutches when they upgrade the IMS, and our of fear, do not wait until the clutch is slipping. I have seen a few get 80,000 miles out of their clutch, but mine was replaced at 30,000 when I had the IMS solution done, which was no where near its expiration. The boxster clutch is pretty durable, so it should reasonably have a long life if driven properly.

If you place it in 3rd gear while moving slow and press the accelerator down and the RPMs jump up with very little accelation, the clutch is done.

 

Since you drive freeways a lot, I am guessing the clutch can last over 90k mi

 

Hard to define what is reasonable. Some owners appear to be willing to accept the clutch should or has to be replaced every so often. I've come upon recommended change by miles of between 40K to the sky's the limit but most often at or under 100K miles.

Clutch life is highly dependent upon how the car is driven, how the car is used, that is how the clutch is used.

I have been driving manual equipped cars since Day #1 and have never worn out a clutch. I had one -- in an '89 Tempo -- slip at under 20K miles but this was due to a lousy clutch and the clutch was replaced under warranty.

I have had one throw out bearing go out. 'course, I replaced the clutch hardware when the TO bearing was replaced. I do not recall the condition of the clutch but the car -- '96 Mustang GT -- had around 140K miles on it.

Based on my personal experience with my 2002 Boxster I can tell you "reasonable" for me is 295K miles and counting. Yes, the clutch is original and the car has covered that many miles.

It is not only the Boxster: I had my 2003 Turbo in for a RMS at 120K miles. The clutch disc had no measurable wear. I measured it with a depth mic. The tech said the disc looked like new.

Common signs a clutch is failing? Well, barring any noises emanating from the bell housing which could be the case if a clutch disc has failed or something else -- release bearing for instance -- has failed slippage is probably the number one symptom.

If one is on the road and say in 4th gear and moving along at around 3K RPMs and floors the gas pedal if the engine revs climb with no corresponding increase in vehicle speed that is clutch slippage. The clutch is done. If the clutch slips there is no reason to keep testing it. Too much slippage can heat damage the flywheel. Besides the clutch won't get better. Bust out the piggy bank and book the car in to get the clutch renewed.

Another sign the clutch might be on its way out is if it becomes grabby. My tech sources tell me this can happen if the clutch wears to the point the rivets of the friction disc are contacting the flywheel or pressure plate.

This does not mean the flywheel has to be replaced. I was told when I asked to see the flywheel (to photograph it) it was out being resurfaced. Even though the rivets had worn into the flywheel some the tech said the FW could be resurfaced and reused. This was after he had checked the operation of the dual mass feature and found it to be still good.

Bear in mind that a grabby clutch could just be the fluid. The brake and clutch fluid are shared between the two systems. The brake fluid should be flushed/bled every 2 years. At the same time the clutch hydraulic system should also be flushed and bled.

Not all clutch grabbiness is the same: Some time back the clutch on my Boxster became grabby, hard to smoothly engage. No matter how hard I tried I could not get the clutch to engage smoothly. This behavior was contrary to its normal behavior. Additionally, shifting got less smooth. It felt as if I was not pushing the clutch all the way down. Even when I focused on doing this though the shifting was just not that good.

I assumed at the miles it was the clutch perhaps even the transmission finally showing signs of wearing out. I have had the transmission fluid changed regularly but I was thinking that fluid changes won't hold off the inevitable forever.

At the dealer talking with the SM about this and he looked up my car's service records and found it had been 2.5 years since I had the brake/clutch fluid flushed and bled. I'm thinking what difference can a half a year make but decided to throw a brake and clutch fluid service at the symptoms before opting to have the clutch renewed so I booked the car in and had this done and afterwards the transformation was quite remarkable. All the clutch grabbiness and less than smooth engagement was gone. Shifting had improved too, had gone back to its previously hot knife through butter smooth.

Might add braking feel and action before and after the bleeding was unchanged.