montoya

I'm not the original owner, so I don't think it's me. My gearbox is getting a new R&P installed at Rothsport and they found a worn out first gear synchro plus a "tired" second synchro Replacing both now, second probably due to rushed shifts but first is odd. Second will get the steel synchro instead of the cheap brass one used in the 997's.

fc-racer

There was a bad batch of synchros in the 2007 model year cars. I was one of the first to suffer through it, including the usual "blame the customer at any cost" Porsche attitude. It was only after they had a few come in for the same issue did they admit there was a material defect. On my car, it happened with only 6k miles.

P.J.S.

agree with North Van below
Mine is getting this now

NorthVan

Montoya, do the cup steels in 1-3, bit the bullet and get it done. I have 2 and 3 done, should have done 1st as well.

Stock are a brass, and very soft, they allow for smoother shifting, but will wear out quickly.

montoya

thanks, I'll look into it.

aero997c2s

Are there any signs of failure? Or can you only tell when trans is out?

NorthVan

shifting grinds when changing gears

RollingArt

Synchro wear is directly related to driving style. There really is no reason for a 1st gear synchro to wear out. 1st gear is only used when getting the car rolling from a stop. It's never used while driving around or track driving.

The synchros see their wear on downshifts, when the throttle has not been blipped during the second clutching of a double clutch down shift. This blip, that happens with the tranny in neutral and the clutch pedal up, matches up the speeds of the two gears you are about to engage. If the driver does not do this matching up of the gears rpms then the syncros go to work and have to spin up the next gear selection using the friction of the spinning synchro against a more or less stationary gear. That is a lot of friction and wear happening to the poor synchro.

1st gear synchro wear is especially easy to avoid. As I've mentioned, 1st is only used after the car is stopped. 1st gear synchro wear happens when the driver engages 1st gear while the car is still rolling to a stop. I think most drivers are prone to shifting into 1st in this manner. To extend 1st gear synchro life to practically forever, just wait for the car to stop before shifting into 1st. If you apply the shifting pressure right as the car hits 0 mph you can feel the transmission just fall right into first. No muss, no fuss for the synchro. You know that pressure you feel while trying to shift into 1st gear while the car is still rolling? Almost like something is pushing back on your shifter? That's the feel of working your 1st gear sychro mercilessly, grinding the heck out of it just so you can select 1st gear before coming to a stop. Stop shifting into 1st gear while the car is still rolling and 1st gear synchro wear will be a thing of the passed.

Not saying you drive your car this way, but most drivers do. Maybe most who are reading this thread.

Side note. I double clutch all my down shifts (except 1st, which I do after I'm stopped) to make life easy on all my synchos. I can bet dollars to donuts that my car will never suffer a synchro problem while under my ownership.

YMMV - Good luck

996FLT6

Wouldn't 1st gear drag launches cause synchro wear in 1st and 2nd? Mike

RollingArt

There is no synchro wear as you leave 1st gear. Probably some wear to 2nd syc as shifter is forced into 2nd gear.

There is much less wear shifting UP through the gears at higher RPMs as the two gears you are engaging are naturally synced up.

GTgears

As Rolling Art says, the only way to put wear onto the 1st gear synchro is to shift into 1st gear before you come to a complete stop on decel.

Or, if like PJ, you have a tall 1st gear in there that you might be using on track in tight hair pins, then you will downshift into it like any other gear in the box.

If you have a stock mainshaft and the useless 3.818 1st gear ratio there is no reason to spend the $2000 it takes to put motorsports steel synchros in there. Save that money for new tires or brakes.

NorthVan

I think that Montoya is adding a new R&P (cheater part).

He would be better doing a CL delete then a saving for more brakes and tires

GTgears

So, a short ring and pinion makes the already too short 1st gear even shorter.

There's a reason the Cups run a 3.167 1st with their 4.00 ring and pinion.

NorthVan

I agree that the stock first gear is too short with a 4.0, I don't use it on the track (once moving), but on the street, in the city, I use it a lot. I spent the money to open the transmission, should have spent the extra $ to do the complete job.

GTgears

Tap throttle in neutral as you roll to the light, feel for it to synch up, slot into 1st and wala, saved you $2000...