Average Life of Transmission (5 Spd)? Clutch?

[pk2]

Hello,

I'm looking at a replacement with 5spd. trans. with 70k on it and which supposedly has good sychos. (no crunching and no howling) and am wondering about how much more life is likely on it.

-What kind of life can be expected from and early 98 5spd (with 70k)?

-Will it stay that way for another 15-20k with mainly easy shifting?

-Can sychros go out with a bang or just fade on these?

-Are they known to just fly apart at all?

Clutch:

-Also, does Porsche have a recommended interval for a clutch change?

-What life can really be expected for a clutch?

-Tolerances?

-Any reason to replace pressure plate at 37k?

Regards & thanks, PK

[JFP in PA]

The realistic “sweet spot” for a 986/996 clutch is in the 40-60K range. Some don’t make it that far, some go further; a lot depends upon the driver.

The 5 speed gear box (assuming proper maintenance and a decent driver) can last for a very long time; syncro failures are very few other than those caused by using the wrong gear oils or flat out abuse.

Keep in mind that anytime you pull the gear box and/or clutch is the best time to do the RMS and the IMS………………

[pk2]

Thank you,

Are pressure plates pretty durable (assuming a clutch hasn't warn to the rivets)? and is there a spec for minimal...tolerance(?) or thickness for a clutch plate?

Regards, PK

[pk2]

1

Edited November 1, 2010 by pk2

[JFP in PA]

Thank you,

Are pressure plates pretty durable (assuming a clutch hasn't warn to the rivets)? and is there a spec for minimal...tolerance(?) or thickness for a clutch plate?

Regards, PK

I'm sure there are wear specs for both; unfortunately, everyone of the discs I've had the pleasure to take apart was obviously toast, and it isn't worth the effort to skimp on only replacing the disc..........do it right and replace both, plus the dual mass flywheel if that has become loose as well..............

Edited November 1, 2010 by JFP in PA

[Dr.Strangepork]

If the other parts are fine, replace at least the disc - it's the part that's cheapest to replace out of the clutch friction surfaces (about $200) and it's also the one that typically sees the most wear. Might as well put one in so you don't have to worry about taking the trans off for another 50k!

When I did mine I replaced just the disc, throw out bearing and pilot bearing, as the flywheel/pressure plate didn't show any scoring or heat damage. Flywheel's dual mass springiness still seemed intact too. Certainly wasn't worn enough to merit the $700 replacement.

As for longevity, my clutch disc had just over 50k of use in an urban environment and it still worked fine but was visibly worn and approaching the end of its useful life. Replacing it with a new disc significantly improved the engagement, shifts like a champ now :)

Edited November 2, 2010 by Dr.Strangepork

[Orient Express]

On average, I get 150, 200K miles out of a clutch assembly.

[teamwenz]

I have 98,000 miles on my car and the clutch is about half worn out.

[pk2]

Thanks all…my computer threw a …IMS on me. Been gone awhile

Quite a divergence; 40 to 180k for the whole shot. With 37k on my car and a lot of double clutching, very little fanning, for $200+ I guess it's worth a few minuets to compare my clutch thickness measurements with a new one.

Regards, PK

[JFP in PA]

You have to look at the perspective of the posters; an individual is working from a sample of one, a shop is looking at it from a sample of many. The individual will always see their perspective as "overwhelming evidence" for their opinion positions, which is totally understandable.

How long the clutch lasts has several dependencies; the driver, the environment the car is normally in (city vs. rural driving), is the car tracked or not, is it driven in the winter snows, etc. etc. Some drivers easily go well over 100K with the factory clutch; but most don't. We often have had to pull a clutch for other reasons (RMS update, IMS issues, transmission problems, etc.) only to find very significant wear on the disc in the 40-60K range (worn down nearly to the rivets). Would these assemblies continue to work in that condition? Most probably yes, but for an "undefined period of time". We have had cars come in for chattering clutch complaints, which turned out to be dual mass flywheel issues, but also had totally burnt discs. Once you have committed to paying someone to pull the gearbox and clutch, the question you have to ask yourself is do you feel confident putting significantly worn components back in to save a few bucks? If you plan to shortly get rid of the car, the answer is obvious. If you plan to keep if for a while, a bit more reflection on the economics of doing so is required. The same process applies to the RMS and IMS updates; you are already there, the money to get at them is already spent, so is the additional $20 bucks for the latest RMS and another $500-600 for the IMS update (plus some additional labor, around 2 hours) and you can sleep soundly, knowing your M96 is going to be fine for many years to come. An interesting data point is that many Indies are doing a full clutch and flywheel replacement, including a new RMS/IMS, for less than the dealers are getting for just a disc replacement. Jake Raby quoted a little over $3K on another website for everything, including before and after dyno pulls.

At the end of the day, it is your car and your budget, and you have to determine where the economics are in your case……...

[pk2]

You have to look at the perspective of the posters; an individual is working from a sample of one, a shop is looking at it from a sample of many. The individual will always see their perspective as "overwhelming evidence" for their opinion positions, which is totally understandable.

How long the clutch lasts has several dependencies; the driver, the environment the car is normally in (city vs. rural driving), is the car tracked or not, is it driven in the winter snows, etc. etc. Some drivers easily go well over 100K with the factory clutch; but most don't. We often have had to pull a clutch for other reasons (RMS update, IMS issues, transmission problems, etc.) only to find very significant wear on the disc in the 40-60K range (worn down nearly to the rivets). Would these assemblies continue to work in that condition? Most probably yes, but for an "undefined period of time".

Thanks JFA always appreciate your input.

I am not arguing for the stupidity of saving $200 for an extra yr of blind bliss clutch wise , only to have to do 90% of the work done again the next year after things have compounded, rivets ground into the pressure plate etc. For me it's only a calculus, a little arithmetic and informed judgment. Bucks a buck. If I've worn off 30% off the clutch in it's 37k-11 yr. life, odds are the clutch is probably going to out live the car under my feet. I don't use the clutch much, get the car rolling and match RPM an MPH, brakes are cheaper than clutches and sychros, the engine doesn't care much which direction the strain is coming from... I.M.O

Of course these are anecdotal, the comments' here (though no-ones piped in with"40k and my ef'n clutch's gone!" (unlike the steady droan regarding whole motors elsewhere here)). I have to consider any shops observations as anecdotal to, albeit to a significantly lesser degree but still not really a scientific sampling…but again who cares, the clutch is going to be what it is. II'll make the call when I see it.

I'm planing to do it myself at this point, sure taken on worse. Self employed, recession, healthy dose of experience and horse sense…'nuff said? Based on a longish absence from this kind greasy stuff, some uncertainty regarding of the IMS/RMS stuff, and some naivete with regards to this fancy sounding pressure plate, I'm thinking a weekend…

How long the clutch lasts has several dependencies…with the factory clutch; but most don't. We often have had to pull a clutch for other reasons (RMS …only to find very significant wear on the disc in the 40-60K range.

Interesting, I'll find my case when I measure it. i'd wonder from my naive position if the IMS threw oil all over the clutch making it slip and chatter and look very very burnt like main seals used to do in another life, but that's a divergence

… An interesting data point .. Jake Raby quoted a little over $3K on another website for everything, .. including before and after dyno pulls.

Interesting indeed! Wonder the significance a bearing and a few seals(out of hundreds) might be for someone's dyno numbers? If there's any at all, I'd think someone has had they're thumb on the scale…no?

At the end of the day, it is your car and your budget, and you have to determine where the economics are in your case…

I'll add creepeconomics. "if your going to have heart surgery, mys well do the kidneys, lungs, gallbladder, etc. while your opened up."

Thanks and Regards, PK

Edited November 8, 2010 by pk2