2005 Boxster Gear Grind
 

hello all:


I've got a dilemma with my Porsche dealer. I would like for them to fix my transmission and they are giving me a hard time. I purchased a 2005 Boxster with 20,000 miles on it, and every time that I shift from 2nd to 4th gear as the car is approaching it's redline the car's transmission makes a grinding sound as if the synchro is not up to the task. If I shift from 2nd to 3rd and the to 4th there is no problem. Also, if the car is below 5000 RPM and not near redline the 2nd to 4th gear happens without that grinding. I'm of the opinion that something is wrong with this synchro and I would like to get it fixed under the factory warranty. They tell me the car is designed to go from 1 to 2 to 3 to 4 to 5. I disagree. What are your thoughts? Thanks so much.

While it shouldn't matter that you upshift from 2-4, the real question is Why? What does one benefit from a redline 2nd gear to an upshift in 4th? Were you raised on drving GM transmissions that would lock out 2-3 and go from 1-4 if driven softly?

I would side with the dealer that your driving style is questionable, which then would make the dealer wonder what other driving habits you have.. so in the end, it sounds like they don't want to fix your "problem" because of perceived abuse of the car, rather than a fault with the design/product.

Are you trying to put it into 4th quickly and back on the gas or or you waiting a second or two and letting the revs drop? If you aren't waiting you are putting A LOT of strain on your clutch and drivetrain by skipping 3rd.

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2nd to 4th is a good shift to get once you up to highway speed and you're still in the power band. Going to 5th puts you out of the power band at 70 mph. If I wanted to keep accelerating to 100 mph and beyond 3rd is the gear of choice, of course. That's the only reason I do it. And the car has never been abused by me. Keep in mind I just bought this thing 5 months ago, if anything it was abused by the 1st owner and the factory warranty needs to respond.

Are you trying to shift quickly or are you waiting for a second or two like you should be?

The 1st to 2nd gear shift is quick since I'm trying to get up to 60 mph or 70 mph quick, but once I'm up there - with the rest of traffic - I'd like to accelerate at a more reasonable pace. 3rd offers too much power and 5th not enough. 4th is the perfect gear for decent highway acceleration. And my shift to 4th is in no way rushed or delayed. This is my 1st porsche. I have a 2000 3 series, manual transmission, no problem. I also had a 1991 accord manual transmission, no problem.


To answer racer's "Why" again is that 2nd gets you to highway cruising speeds. Of course if I wanted to keep going (100 mph +) I would go to 3rd.

Do you double clutch going from 2-4? This might help as it would slow down the shift and prevent a gnashing of the gears.

In your example I understand why you do it. I have done it myself on occasion, without a grind, but with a slow deliberate shift. You need to give the synchros time to do there job. My feeble mind says that if you shifted to third, you would be fine, but given the placement of the gears, and the large difference between the rates that they are spinning (lets say the car is at 6500rpm in 2nd but drops to 3500 in 4th, IS part of the problem. 4th gear is spinning at a demonstrably lower rate, if you consider that 3rd gear would be at, say, 5000rpm. You need to allow time to let the transmission catch up.

In addition, since the car is "used", what specifically does your warranty say about transmission repair? Not what you "think" it says, but what it actually says.

2nd to 5th No problem.
 

With this logic a 2nd to 5th gear should grind even more, but it does not grind at all.