Gear 1-2 grind
03-20-2021 | 10:26 PM
#376
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Thanks, WC. It "graunched" again today (1st to 2nd, as always), just when I was thinking I'd found the answer. As I was rethinking this, it occurred to me that I didn't have a "graunch" until 1,100 miles when I started increasing the max revs over 4,000. Maybe that has something to do with it? Also, I think you may be onto something with shifting more slowly. Could it be the synchros need more time to break in, after the motor is revved above 4,000 in 1st and then one shifts to 2nd?
In my GT4, 75mph in 6th occurs at 3,000rpm, and the car is surprisingly comfortable at that speed. I won't say it's quiet, but it is comfortable. Then again, I love the noises made by a great internal combustion engine. I really don't miss the 7th gear in my 991.2 911 C2.
God bless,
TT
In my GT4, 75mph in 6th occurs at 3,000rpm, and the car is surprisingly comfortable at that speed. I won't say it's quiet, but it is comfortable. Then again, I love the noises made by a great internal combustion engine. I really don't miss the 7th gear in my 991.2 911 C2.
God bless,
TT
I really only notice it when I am fast shifting above 4000 RPM, below that the syncros seem to have time/ability to get things together, combined with the fact that shifts generally below 4000 RPM are when I am driving in a less spirited nature if you know what I mean!
As for the distance (or number of shifts really) needed to have the 1-2 syncro properly broken in, I am not sure what this could be, some people say it all cleared up at 1000 miles or so, I am just about to 3000 miles and it seems like it is still there to me.
03-20-2021 | 10:45 PM
#377
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From: In Mass (as in church)
I believe that it is RPM related:
I really only notice it when I am fast shifting above 4000 RPM, below that the syncros seem to have time/ability to get things together, combined with the fact that shifts generally below 4000 RPM are when I am driving in a less spirited nature if you know what I mean!
As for the distance (or number of shifts really) needed to have the 1-2 syncro properly broken in, I am not sure what this could be, some people say it all cleared up at 1000 miles or so, I am just about to 3000 miles and it seems like it is still there to me.
I really only notice it when I am fast shifting above 4000 RPM, below that the syncros seem to have time/ability to get things together, combined with the fact that shifts generally below 4000 RPM are when I am driving in a less spirited nature if you know what I mean!
As for the distance (or number of shifts really) needed to have the 1-2 syncro properly broken in, I am not sure what this could be, some people say it all cleared up at 1000 miles or so, I am just about to 3000 miles and it seems like it is still there to me.
God bless,
TT
Last edited by TomTarzian; 03-20-2021 at 10:47 PM.
03-20-2021 | 10:55 PM
#378
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03-20-2021 | 11:17 PM
#379
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I think that it’s a little bit of mental training and not the system adjusting over time. Initially I lived in fear shifting into 2nd and hearing that grinding, 😭 but the trick for me was taking my time going into 2nd. Over a course of a couple hundred miles, it became second nature and no more grind.
God bless,
TT
03-21-2021 | 07:01 AM
#380
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My Spyder is 4500km, I don’t track it but I drive it hard. Over the last 200km, most of the time the gears are butter smooth even 1-> 2 at 7000rpms.
However, I’ve had 3 instances in which getting into 2 was impossible!!! 2 instances heavy breaking in 3rd at 5000rpms and downshifting to 2 and 1 instance up shifting from 1 to 2 at ~5000rpms.
I just put in Neutral and go back to 3rd then 2nd gear and it works fine.
I will inform my dealership and give it another 2000km, if it happens again more than 3 times, I will start with a gearbox oil change and see how it improves.
However, I’ve had 3 instances in which getting into 2 was impossible!!! 2 instances heavy breaking in 3rd at 5000rpms and downshifting to 2 and 1 instance up shifting from 1 to 2 at ~5000rpms.
I just put in Neutral and go back to 3rd then 2nd gear and it works fine.
I will inform my dealership and give it another 2000km, if it happens again more than 3 times, I will start with a gearbox oil change and see how it improves.
03-21-2021 | 11:18 AM
#381
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I think that it’s a little bit of mental training and not the system adjusting over time. Initially I lived in fear shifting into 2nd and hearing that grinding, 😭 but the trick for me was taking my time going into 2nd. Over a course of a couple hundred miles, it became second nature and no more grind.
So can we infer from your comments that you have experienced the 1-2 grind?
03-21-2021 | 11:22 AM
#382
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My Spyder is 4500km, I don’t track it but I drive it hard. Over the last 200km, most of the time the gears are butter smooth even 1-> 2 at 7000rpms.
However, I’ve had 3 instances in which getting into 2 was impossible!!! 2 instances heavy breaking in 3rd at 5000rpms and downshifting to 2 and 1 instance up shifting from 1 to 2 at ~5000rpms.
I just put in Neutral and go back to 3rd then 2nd gear and it works fine.
I will inform my dealership and give it another 2000km, if it happens again more than 3 times, I will start with a gearbox oil change and see how it improves.
However, I’ve had 3 instances in which getting into 2 was impossible!!! 2 instances heavy breaking in 3rd at 5000rpms and downshifting to 2 and 1 instance up shifting from 1 to 2 at ~5000rpms.
I just put in Neutral and go back to 3rd then 2nd gear and it works fine.
I will inform my dealership and give it another 2000km, if it happens again more than 3 times, I will start with a gearbox oil change and see how it improves.
I have had many MT cars, this is the worse for being a real bear when cold...
So same question to you as well DocMo, have you experienced the 1-2 shift grind?
03-21-2021 | 11:59 AM
#383
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03-21-2021 | 12:13 PM
#384
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Impossible!? that is strange, the only time I experience this is on a cold morning when the transmission oil is very cold and the transmission really doesn't want to sift into second, it needs to warm up!
I have had many MT cars, this is the worse for being a real bear when cold...
So same question to you as well DocMo, have you experienced the 1-2 shift grind?
I have had many MT cars, this is the worse for being a real bear when cold...
So same question to you as well DocMo, have you experienced the 1-2 shift grind?
03-21-2021 | 12:40 PM
#386
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03-21-2021 | 12:43 PM
#387
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Sounds similar to what e9xM owners experienced, myself included. Usually shows up during a fast 8000 RPM 1-2 shift. I chocked it up to the big RPM delta and synchros that are a little underspec'd for my liking. (1-2 will have the biggest delta) Like the GT4, it's not a drag race car, but I wasn't happy that the issue exists. I could modulate it with regular transmission fluid changes, but sounds like this is happening on cars with fresh fluid.
03-21-2021 | 12:47 PM
#388
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No I don’t regret it. If you plan to seriously track, you might want to start thinking about how to improve the transmission.
03-21-2021 | 12:51 PM
#389
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To put the 1-2 grind into perspective, for me it is a less than 1% issue... a split second delay is all that is required to mitigate its intrusion, now making it 0%.
The discussion here for me is one of curiousity and discovery.
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AlexCeres (03-21-2021)
03-21-2021 | 12:54 PM
#390
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From: Bay Area
@ Enduro. Interesting that you mentioned that. My E92 M3 would always feel better after a fluid change but seem to get back it’s notchiness quickly. Been driving it for the past 12 years with a tad over 104k miles, a lot of track days. I have been driving manual for 25 years and pretty good with heel and toe. Sometimes I find myself forcing gears while on the track grinding be damned in that car. Definitely not a great experience.
Last edited by Thinker23; 03-21-2021 at 01:02 PM.