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7-Speed Manual - 2nd Gear Synchro Issues - Anyone?!?!

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Old 06-15-2012 | 10:45 AM
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Default 7-Speed Manual - 2nd Gear Synchro Issues - Anyone?!?!

How may of you have a 7-speed manual car with a stubborn grinding synchro that grinds unless you granny shift from 1-2? The car had 8 miles when it first happened and it's not getting worse. My first thought was premature attrition of maybe a synchro but I'm wondering if it's poor gear alignment given that it's PDK based. None of the shifts generate problems. Just 1-2.

Anyone else?
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Old 06-15-2012 | 02:05 PM
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No problems here....
Old 06-15-2012 | 03:06 PM
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always had that feeling with M/t's... if you are higher in rev's it's fine right? just notchy when you try and shift quick at low rev's 1->2?

just feather it more... usually i would pull down to 2 (not into 2 but just before) and blip the rev and then you can slide right in.... it for some reason it's not that, maybe a problem w/ your car.. but my 997.1 always would grind into 2nd if i forced it.. but if i was gentle it was perfect every time..
Old 06-15-2012 | 06:51 PM
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I don't have this issue either on mine but I would give it some time to break in before you go to the dealer with it.

My car has 1,000 miles on it and I do notice it is smoother as far as shifting ...
Old 06-15-2012 | 08:01 PM
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I wouldn't consider that normal. Agree that 1-2 can be notchy at low RPMs, but I've never had anything I would describe as "grinding". It's just a firm "catch" going into 2nd.
Old 06-16-2012 | 12:40 AM
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no problem here
Old 06-16-2012 | 12:58 AM
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1000miles on my 991C2S MT, shifting is very smooth between all gears, no grinding whatsoever. Shifting is less notchy than my 997.2
Old 06-16-2012 | 01:41 AM
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I'm at 4000 miles, no problems here. It feels different when shifting to 2nd at different RPMS but that is normal I'm Sure
Old 06-16-2012 | 01:17 PM
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I'm familiar with the symptoms you're describing as I had them on a 996 GT3 as well. My 991 does not feel this way at all - the shifter is very smooth going into any gear. Not good news in a way, but at least you can tell the dealer that others aren't having the issues you are.

Jim
Old 06-18-2012 | 12:47 PM
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Something is definitely not right in the trans. While it's not as bad as it once was, we all know why that is, because i've been doing damage.

Glad to hear that I am the only one and that problems aren't across the board. Given that the stack in the 991 manual was adapted from the PDK, whose gears aren't numbered in traditional H-pattern order, I have read that the new system requires that when shifting from 1st to 2nd, "the special layout of the shift fingers on the actuator shaft means that when shifting from 1st to 2nd gear, the rotation simultaneously moves the shift frames of the respective gears."

I'm assuming that it's out of alignment by the smallest bit and requires a very slow shift. While it's more prone to happen at lower RPMs, slowing the shift down avoids it. we aren't talking speed shifts here either. And it's just this gear, but that makes sense that the 1-2 shift is completely unique in the 7-spd manual car.
Old 07-23-2017 | 03:25 AM
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Default 2nd gear grind / crunch

Originally Posted by BGB Motorsports
Something is definitely not right in the trans. While it's not as bad as it once was, we all know why that is, because i've been doing damage.

Glad to hear that I am the only one and that problems aren't across the board. Given that the stack in the 991 manual was adapted from the PDK, whose gears aren't numbered in traditional H-pattern order, I have read that the new system requires that when shifting from 1st to 2nd, "the special layout of the shift fingers on the actuator shaft means that when shifting from 1st to 2nd gear, the rotation simultaneously moves the shift frames of the respective gears."

I'm assuming that it's out of alignment by the smallest bit and requires a very slow shift. While it's more prone to happen at lower RPMs, slowing the shift down avoids it. we aren't talking speed shifts here either. And it's just this gear, but that makes sense that the 1-2 shift is completely unique in the 7-spd manual car.
@bgb
Did this amount to anything? I recently acquired a used white 991.1 from NYC and it has this same issue at low speeds, only 2nd gear. Rare, and definitely not consistent but only affects 2nd gear.
Old 07-23-2017 | 09:42 AM
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Mine shifts just fine.
Old 07-23-2017 | 10:47 AM
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Grinding synchros are never going to get any better - in the very early 911's that was commonplace (my 1970 911E did it) and they required transmission rebuilds every 100K miles or so. That issue was solved long ago, shouldn't be happening with a 991. Probably a misaligned gear shaft or a bent shifting fork. Time for a warranty repair.
Old 07-23-2017 | 11:27 AM
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Originally Posted by BGB Motorsports
How may of you have a 7-speed manual car with a stubborn grinding synchro that grinds unless you granny shift from 1-2? The car had 8 miles when it first happened and it's not getting worse. My first thought was premature attrition of maybe a synchro but I'm wondering if it's poor gear alignment given that it's PDK based. None of the shifts generate problems. Just 1-2.

Anyone else?
How are 4, 6, and R? I had mine go out on the back straight at VIR, lost all even gears. This started as bad lock-in then grinding into R, it then progressed into 4th (the 3 to 4 shift at VIR is where I completely lost the even side drivetrain).

Good news, CPO replaced the transmission. Bad news, there was no discussion of the actual problem due to the complete swap out.

BTW - I did have a bit of a 'clunk' when mid shifting (in town around 2 to 3K) from 1 to 2. No clunk in the new tranny. I bought this car used and it did have a Level 5 over rev
Old 07-23-2017 | 11:51 AM
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Originally Posted by Eddie Hsu
@bgb
Did this amount to anything? I recently acquired a used white 991.1 from NYC and it has this same issue at low speeds, only 2nd gear. Rare, and definitely not consistent but only affects 2nd gear.
Porsche, being the awesome car manufacturer that they are, replaced the gearbox knowing of the potential issue; it was all under warranty. Everyone I spoke to that had the problem that got a new gearbox has been issue free, myself included!


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