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      07-11-2011, 01:40 AM   #1
m3heaven
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Exclamation 6MT: Problem Downshifting into 2nd Gear

Hey Guys,

Has anyone else had any problems downshifting into 2nd gear from 3rd while driving relatively fast?

During my last two track days, I've had a really hard time heel-toeing/rev-matching into 2nd gear from 3rd. It doesn't grind but it just locks me out of 2nd as if the gate is closed. This only happens when I'm driving on the track or fast on the streets. I have no problems going into 2nd while just cruising around.

Any known solutions for this problem?

Thanks!

Last edited by m3heaven; 07-11-2011 at 02:04 AM.
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      07-11-2011, 01:58 AM   #2
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no.. not for me.
try royal purple transmission fluid. that seemed to smooth things out for me..
maybe you're too high of an RPM.
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      07-11-2011, 02:03 AM   #3
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Quote:
Originally Posted by saeedg48 View Post
no.. not for me.
try royal purple transmission fluid. that seemed to smooth things out for me..
maybe you're too high of an RPM.
Not really an issue of RPM. Usually when I'm trying to downshift I'm anywhere from 2.5-4.5k RPM in 3rd. Regardless it's a manual so it should go in any RPM lol
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      07-11-2011, 05:52 AM   #4
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Quote:
Originally Posted by m3heaven View Post
Hey Guys,

Has anyone else had any problems downshifting into 2nd gear from 3rd while driving relatively fast?

During my last two track days, I've had a really hard time heel-toeing/rev-matching into 2nd gear from 3rd. It doesn't grind but it just locks me out of 2nd as if the gate is closed. This only happens when I'm driving on the track or fast on the streets. I have no problems going into 2nd while just cruising around.

Any known solutions for this problem?

Thanks!

Just floor the clutch harder!! it will def help!
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      07-11-2011, 08:08 AM   #5
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Does it happen while hard cornering i would assume that since you mentioned heel toe?
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      07-11-2011, 02:41 PM   #6
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Second is notchy on this car man, be it from 1-2, 3-2 or 4-2. Plus going cross-gate from the middle is quite tricky too. This is quite obvious on the 4-5 shift. If you don't get it perfectly right, you can feel the notchiness (the lever hitting the sides of the gate, I guess), making it harder to go in smoothly. Second is the same way. Problem is the sweet spot is not at the end of the lever stop, so it's very hard to consistently get it right (in both 2nd and 5th). All other gear changes are consistently smooth as butter in my car, especially after I also switched to RP Synchromax oil.

I've never grinded a gear, but have never shifted aggressively either (like on a track). It's just a matter of programming your brain to givie more time to the 2nd gear shifts (both up and down) to avoid releasing clutch too soon and grinding. I've driven 3 M3s, and all 3 cars behave like mine, so it's the nature of the beast. And most of the many manual cars I've owned had a notchy 2nd, so it's not uncommon. Only car I've driven (but not owned) that didn't notice this behavior was on the Porsche Cayman S and 911s. Best transmission IMO, but not a great shifter, although it does the job perfectly. Good luck.
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      07-11-2011, 03:23 PM   #7
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Quote:
Originally Posted by img View Post
Does it happen while hard cornering i would assume that since you mentioned heel toe?
It's happening whenever. But usually when I'm trying to downshift it is when I'm braking before the turn...so when I'm going straight. And since it doesn't go in I end up having to go into neutral mid turn and stick it back into 3rd at the end haha. It sucks ><
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      07-11-2011, 03:26 PM   #8
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Quote:
Originally Posted by elp_jc View Post
Second is notchy on this car man, be it from 1-2, 3-2 or 4-2. Plus going cross-gate from the middle is quite tricky too. This is quite obvious on the 4-5 shift. If you don't get it perfectly right, you can feel the notchiness (the lever hitting the sides of the gate, I guess), making it harder to go in smoothly. Second is the same way. Problem is the sweet spot is not at the end of the lever stop, so it's very hard to consistently get it right (in both 2nd and 5th). All other gear changes are consistently smooth as butter in my car, especially after I also switched to RP Synchromax oil.

I've never grinded a gear, but have never shifted aggressively either (like on a track). It's just a matter of programming your brain to givie more time to the 2nd gear shifts (both up and down) to avoid releasing clutch too soon and grinding. I've driven 3 M3s, and all 3 cars behave like mine, so it's the nature of the beast. And most of the many manual cars I've owned had a notchy 2nd, so it's not uncommon. Only car I've driven (but not owned) that didn't notice this behavior was on the Porsche Cayman S and 911s. Best transmission IMO, but not a great shifter, although it does the job perfectly. Good luck.
So do you think this is normal? And not a more severe case of my 2nd gear being worse than other people's cars? Maybe my 2nd gear synchro is bad? I don't know....

I don't have trouble downshifting into 2nd driving slowly. Sometimes its notchy but it never locks me out.

Did the ZHP shift knob help with the 2nd gear?
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      07-11-2011, 03:55 PM   #9
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weird so you mean when your in 3rd and put it on 2nd at high speed it locks you out?

i never had that happen although it is hard to put the gear in 2nd doesnt matter what gears your coming from.
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      07-11-2011, 04:26 PM   #10
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weird so you mean when your in 3rd and put it on 2nd at high speed it locks you out?

i never had that happen although it is hard to put the gear in 2nd doesnt matter what gears your coming from.
Not necessarily high speeds. But I think 50mph~
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      07-11-2011, 04:31 PM   #11
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So do you think this is normal? And not a more severe case of my 2nd gear being worse than other people's cars?
A bad synchro is not going to 'lock you out'; it'd grind. And it'd grind at ANY rpm, so you can rule that out.

Only way to know your car is 'normal' is for you to drive another M3, or ask a member to drive yours next to you, since that might be a better sell . If your tranny feels the same, which I suspect will be the case, then you'd know there's no serious problem.

As for the solution, I suspect you might have air in your system, and here's why. For some strange reason, many cars (especially Corvettes) have slave operation affected by high rpm. I have no idea why since I've never seen an exact schematic (and neither on the M3), but it's common. If you have any air in the system, the issue is exacerbated. Just mention this so you know it's another possibility.

Now let's think outloud. Let's say you have a bit of air, and it's bled out. Now instead of being 'locked out', you'd have the infamous grind, which is a very well known problem. And until now I'm thinking it could be the same Corvette slave issue, especially since our engine spins way higher. Owners resolve that issue with the LS7 (Z06) clutch/slave, but I have no idea what's the difference. Or why that phenomenon takes place (anybody?).

I have an idea to try to diagnose the problem. Here's what I suggest you do and report back to us, so we can continue brain storming :

1. Since high engine rpm COULD be the issue, try downshifting to 2nd WITHOUT REV MATCHING. In other words, you'd be fully exercising/testing the synchro.

2. You told us rev-matching doesn't help. Please try double-clutching and see if anything changes.

3. Start a thread and ask a member to please drive your car and his with you next to him under exactly the same conditions (maybe downshift from 3rd to 2nd at 7K rpm? Shouldn't be that fast), using different techniques and different shifting speeds (from quick to slow), and see what he and you think afterwards. And yes, if he offers to let you drive his car, even slowly, all the better so you can compare shifting and clutch action.

I'm pretty sure you won't have an issue doing it slowly, and my guess is mostly due to the engine having slowed down, pointing to the same mystery slave issue than the regular Vettes. But you could be hitting the gate wrong if that doesn't happen in other gears. Let's find out . Good luck man.

Last edited by elp_jc; 07-11-2011 at 04:46 PM.
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      07-11-2011, 04:33 PM   #12
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Maybe I can check it out next time Roy.
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      07-11-2011, 04:37 PM   #13
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Maybe I can check it out next time Roy.
Yeah I was gonna ask to see if you wanted to drive mine and maybe if I could drive yours but I didn't want to ask hahaha. I know most people don't like letting other people drive their cars.

At buttonwillow in the cotton corners I wanted to go into 2nd but everytime I tried it wouldn't let me so I had to go through the turn in neutral and go back into 3rd rofl....fail
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      07-11-2011, 04:44 PM   #14
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Quote:
Originally Posted by elp_jc View Post
A bad synchro is not going to 'lock you out'; it'd grind. And it'd grind at ANY rpm, so you can rule that out.

Only way to know your car is 'normal' is for you to drive another M3, or ask a member to drive yours next to you, since that might be a better sell . If your tranny feels the same, which I suspect will be the case, then you'd know there's no serious problem.

As for the solution, I suspect you might have air in your system, and here's why. For some strange reason, many cars (especially Corvettes) have slave operation affected by high rpm. I have no idea why since I've never seen an exact schematic (and neither on the M3), but it's common. If you have any air in the system, the issue is exacerbated. Just mention this so you know it's another possibility.

Now let's think outloud. Let's say you have a bit of air, and it's bled out. Now instead of being 'locked out', you'd have the infamous grind, which is a very well known problem. And until now I'm thinking it could be the same Corvette slave issue, especially since our engine spins way higher. Owners resolve that issue with the LS7 (Z06) clutch/slave, but I have no idea what's the difference. Or why that phenomenon takes place (anybody?).

I have an idea to try to diagnose the problem. Here's what I suggest you do and report back to us, so we can continue brain storming :

1. Since high engine rpm COULD be the issue, try downshifting to 2nd WITHOUT REV MATCHING. In other words, you'd be fully exercising/testing the synchro.

2. You told us rev-matching doesn't help. Please try double-clutching and see if anything changes.

3. Start a thread and ask a member to please drive your car and his with you next to him under exactly the same conditions (maybe downshift from 3rd to 2nd at 7K rpm? Shouldn't be that fast), using different techniques and different shifting speeds (from quick to slow), and see what he and you think afterwards.

I'm pretty sure you won't have an issue doing it slowly, and my guess is mostly due to the engine having slowed down, pointing to the same mystery slave issue than the regular Vettes. Let's find out. Good luck man.
I don't know if I'll be able to find the time (I walk to work) to find a place to replicate the problem this week but I'll keep the thread updated as soon as I find out.

Thanks for the help! I'm also thinking about swapping out the tranny fluid to something else.
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      07-11-2011, 09:39 PM   #15
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You beat me to the punch-been meaning to post something like this

HOWEVER

I'm willing to bet none of the above resolutions will solve your problem. Your problem is quite simple-BMW put reverse in a horrible location.

Aggressive driving requires aggressive shifting-which in turn leads to throwing the car into second harder than you would driving normally (DUH).

With that being said, when you’re downshifting from 3-2, you’re throwing the shifter over too far and missing the opening for 2nd gear-traveling down the line towards reverse. If somehow anyone’s confused by what I just said-look at the beautiful artwork BMW laid out on your shifter.

Next time you’re driving aggressively be that on the street or track (preferably track), loosen up and relax on that downshift and you’ll feel it come to you as easily as when you’re cruising.

One more thing I should say-being you’re a competent driver-imagine racing as a dance or ballet in how everything flows together seamlessly when the reality isn’t so. Hell, even imagine the music they’re dancing too! Trust me, it’ll calm your nerves, loosen you up and allow you to be a better (and quicker) driver. After all, you want to be graceful right? Not the guy mashing the brakes on and off and missing shifts.

I’m not saying downshift slower, I’m saying be more smooth and calm about it and you won’t overshoot your mark. If you have the means, to speed up the process, get behind the wheel or even passenger in a faster car on the track-it’ll better develop your understanding of speed. The body naturally reacts to what it believes is impending danger-if you can control that reaction by heightening your threshold for danger (speed), you’ll be shedding SECONDS in no time.

Apologies if this came off as a bit cocky and/or angry, but I couldn’t stand going all clutch and brake before finally finding the elusive 2nd gear. If only reverse was on the other side…and to the bottom haha
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      07-11-2011, 09:57 PM   #16
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Quote:
Originally Posted by SLICKTITTLES View Post
With that being said, when you’re downshifting from 3-2, you’re throwing the shifter over too far and missing the opening for 2nd gear-traveling down the line towards reverse. If somehow anyone’s confused by what I just said-look at the beautiful artwork BMW laid out on your shifter.
This was my first thought. It's not that hard to get caught in the reverse gate if you are hamfisting it. You can't push the lever all the way left and down or you can catch the reverse gate and that will definitely feel like you're locked out. You can catch the reverse gate well before actually engaging reverse, especially if you're yanking on the shifter.

If anything on my car the 3-2 downshift is more easily accomplished at high rpm/hard braking.

Tranny fluid change is probably a waste of time.
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      07-11-2011, 10:45 PM   #17
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Quote:
Originally Posted by SLICKTITTLES View Post
You beat me to the punch-been meaning to post something like this

HOWEVER

I'm willing to bet none of the above resolutions will solve your problem. Your problem is quite simple-BMW put reverse in a horrible location.

Aggressive driving requires aggressive shifting-which in turn leads to throwing the car into second harder than you would driving normally (DUH).

With that being said, when you’re downshifting from 3-2, you’re throwing the shifter over too far and missing the opening for 2nd gear-traveling down the line towards reverse. If somehow anyone’s confused by what I just said-look at the beautiful artwork BMW laid out on your shifter.

Next time you’re driving aggressively be that on the street or track (preferably track), loosen up and relax on that downshift and you’ll feel it come to you as easily as when you’re cruising.

One more thing I should say-being you’re a competent driver-imagine racing as a dance or ballet in how everything flows together seamlessly when the reality isn’t so. Hell, even imagine the music they’re dancing too! Trust me, it’ll calm your nerves, loosen you up and allow you to be a better (and quicker) driver. After all, you want to be graceful right? Not the guy mashing the brakes on and off and missing shifts.

I’m not saying downshift slower, I’m saying be more smooth and calm about it and you won’t overshoot your mark. If you have the means, to speed up the process, get behind the wheel or even passenger in a faster car on the track-it’ll better develop your understanding of speed. The body naturally reacts to what it believes is impending danger-if you can control that reaction by heightening your threshold for danger (speed), you’ll be shedding SECONDS in no time.

Apologies if this came off as a bit cocky and/or angry, but I couldn’t stand going all clutch and brake before finally finding the elusive 2nd gear. If only reverse was on the other side…and to the bottom haha
I was trying to do the whole process in a slower movement but because I have such little time to to downshift in the correct place I just never got it right. Next time when I'm on the track (July 30th) I'll try to make a more conscious effort downshifting in a more fluid/slower movement.

And don't worry about my threshold for speed
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      07-11-2011, 11:10 PM   #18
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One thing to check: I've found that with some BMWs in the past, the motor mounts, as the car aged, would allow enough slop for the transmission gates to move relative to the console, making the motion different in corners. check your tranny mounts for wear and consider some stiffer ones?

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      07-11-2011, 11:24 PM   #19
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One thing to check: I've found that with some BMWs in the past, the motor mounts, as the car aged, would allow enough slop for the transmission gates to move relative to the console, making the motion different in corners. check your tranny mounts for wear and consider some stiffer ones?

-kit, who likes DCT
Yeah I was considering stiffer shifter bushings or tranny mounts but I don't know of any aftermarket ones. Plus my car only has 4.5k miles on it haha.
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      07-12-2011, 10:15 AM   #20
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Your problem is quite simple-BMW put reverse in a horrible location.
Actually, the worst location is left/down, for the same reasons you mentioned. Look at the bright side .

And yes, you're absolutely correct that could be happening. In fact, you don't have to go past the reverse detent to hit the side of the gate. That's why I mentioned it's so tricky to get the gate just right, which when you do feels like butter, rather than the notchiness and increased effort typically felt. That's why I also suggested to the OP to let somebody else drive his car, to eliminate technique issues.

By the way, RP fluid makes the most difference when cold. I felt very little difference once at full operating temperature, but enough to notice the extra smoothness.

I'd like to see what the hell Getrag did with the gates on this transmission. Seems to be the gates are squared at the edges, rather than rounded, or something to that effect. That's why is so hard to get a gate on the side shafts (1,2,5,6) perfectly. No other transmission feels as notchy as this one, especially in 2nd and 5th. Go all the way to the left (before the R gate spring resistance) and you hit 2nd left side of the gate. Go all the way to the right and you hit 5th right side of the gate. So it's not misalignment or tranny/engine mount issues. And yes, we're nitpicking, but those little things would have made it almost perfect . A little more mechanical feel would have made it perfect, but it's better than Porsche. Looking forward to more comments.
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      07-12-2011, 10:21 AM   #21
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Listen people. Just do a fuckin burnout and be done with it.
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