6MT ocasional second gear grind

[strokemycocktus]

Since I have owned the car, I happen to have some issues with the second gear. The mileage is 60k kms.
It happens usually after hard acceleration on 1st. It doesn't matter on which rpm I try to shift - it sometimes happens on 4k and sometimes on redline. The gear grinds and locks. No problems on downshifts but I always rev match.
Shifting very gently and a bit slower makes the issue appear less frequently, but it still happens. I also get a slight grind on my first shift in the morning (very slow driving), but the gear eventually engages.
I have changed motor mounts and added F10 M5 knob, slight improvement but problem still occurs. The grind seems like shifting with clutch not fully in, but I am 100% sure it is every time.
I know some owners have reported synchro issues on this gearbox. Not sure if this is the case here, as the grind is clearly load related, not rpm. I am able to get smooth shifts on redline, it usually grinds on lower rpm after heavy acceleration.
My guesses are:
Clutch issue - air, or disengagement problem? It was replaced about 40k kms ago though and seems to be working fine overall.
Transmission mounts - engine mounts were done when replaced, so maybe these are too, and there is too much moment.
Excessive movement in the rest of the drivetrain - diff / rear subframe bushings, could this possibly cause some misalignment in the transmission?

Bottom line is I have a hard time to get repeatable smooth and fast shifts under heavy acceleration. Sometimes it goes great, and sometimes the gear grinds and I look like an ass on the road. I am going to flush the trans oil with redline MTL soon, but the it was already changed 25k kms ago so I don't expect night and day improvement.
Just to note, by shifting fast I don't mean smashing the shifter like a caveman
Any input will be much appreciated.

[94jedi]

seems like you have the basics covered; mounts, fluids, etc. Hate to tell you to throw money at it but what about shifter bushings/SSK? Ultimate clutch pedal? those things will likely only help marginally though. Might be an internal issue w/ the trans. Keep us posted.

[strokemycocktus]

Originally Posted by 94jedi

seems like you have the basics covered; mounts, fluids, etc. Hate to tell you to throw money at it but what about shifter bushings/SSK? Ultimate clutch pedal? those things will likely only help marginally though. Might be an internal issue w/ the trans. Keep us posted.

How could upgraded bushings or an SSK help? To be honest I can't complain for a lot too much movement on the shifter.
I can't also see how a clutch pedal could help me, and this would be the last mod I would do - $300 for a pedal is a bit steep for me.
I will write an update after I put redline MTL and new trans mounts.

[doogee]

Originally Posted by strokemycocktus

How could upgraded bushings or an SSK help? To be honest I can't complain for a lot too much movement on the shifter.
I can't also see how a clutch pedal could help me, and this would be the last mod I would do - $300 for a pedal is a bit steep for me.
I will write an update after I put redline MTL and new trans mounts.

Bushings, SSK or a different clutch pedal isn't going to help. Everything should work correctly with factory parts before you start messing around with aftermarket junk.

If this problem is only in second gear, I'd be leaning towards a shot synchro. Which means you'll need a new transmission.

Try bleeding the clutch slave. Maybe you aren't getting enough travel on the pressure plate. If you have a clutch stop, remove it and see if that makes an improvement.

[Honda]

Originally Posted by doogee

Bushings, SSK or a different clutch pedal isn't going to help. Everything should work correctly with factory parts before you start messing around with aftermarket junk.

If this problem is only in second gear, I'd be leaning towards a shot synchro. Which means you'll need a new transmission.

Try bleeding the clutch slave. Maybe you aren't getting enough travel on the pressure plate. If you have a clutch stop, remove it and see if that makes an improvement.

I agree with his analysis...unfortunately, looks like your synchronous went bad which means new transmission to fix it. Are you first owner? Probably 1st owner didn't know how to drive MT properly..

[Scharbag]

Originally Posted by Honda

I agree with his analysis...unfortunately, looks like your synchronous went bad which means new transmission to fix it. Are you first owner? Probably 1st owner didn't know how to drive MT properly..

Why a new transmission? Or does BMW not sell syncros for this tranny?

Cheers,

[strokemycocktus]

Originally Posted by doogee

Bushings, SSK or a different clutch pedal isn't going to help. Everything should work correctly with factory parts before you start messing around with aftermarket junk.

If this problem is only in second gear, I'd be leaning towards a shot synchro. Which means you'll need a new transmission.

Try bleeding the clutch slave. Maybe you aren't getting enough travel on the pressure plate. If you have a clutch stop, remove it and see if that makes an improvement.

I feel the same way about aftermarket parts. But wouldn't a bad synchro cause problems with shifting on high RPM, rather than load based problems? I can have trouble getting into second even at 3-4k rpm after shord but hard acceleration from standstill. My guess is that it can be apparent only on 2nd gear because there is the highest gear ratio difference between 1st and 2nd. I do get some slight grinds when going to 3rd sometimes, but it doesn't get locked.
I have also tried shifting differently. I need to keep in mind that I am probably still getting used to a new knob, and this trans is definitely a bit tricky when it comes to 1->2 shift. Waiting a fraction of a second longer after the clutch is pressed in, and pulling the lever very gently makes the shift effortless and in most cases smooth - under load and on higher rpm too. This is however something near granny shifting imo. But to be honest, if I end up with a diagnosis that the only solution is changing the whole trans, I guess I will live with a slower 1-2 shift.

Originally Posted by Honda

I agree with his analysis...unfortunately, looks like your synchronous went bad which means new transmission to fix it. Are you first owner? Probably 1st owner didn't know how to drive MT properly..

Not a 1st owner. Seems that I am the 4th. But I have read some posts that people had 2 transmissions changed by the dealer during their ownership. It is either a factory defect on 2nd gear synchro, or just the way this transmission works - rather slow on 1-2 shift. Possibly when you try to rush it the problem gets more serious.

Originally Posted by Scharbag

Why a new transmission? Or does BMW not sell syncros for this tranny?

Cheers,

Nope, BMW does not sell any internal parts for the transmission. I have contacted ZF and they told me this trans is reserved by BMW, so no parts are available if they don't provide them.

[Honda]

Originally Posted by strokemycocktus

Nope, BMW does not sell any internal parts for the transmission. I have contacted ZF and they told me this trans is reserved by BMW, so no parts are available if they don't provide them.

That sucks

[Scharbag]

Originally Posted by strokemycocktus

Nope, BMW does not sell any internal parts for the transmission. I have contacted ZF and they told me this trans is reserved by BMW, so no parts are available if they don't provide them.

Yuck.

[94jedi]

Originally Posted by strokemycocktus

How could upgraded bushings or an SSK help? To be honest I can't complain for a lot too much movement on the shifter.
I can't also see how a clutch pedal could help me, and this would be the last mod I would do - $300 for a pedal is a bit steep for me.
I will write an update after I put redline MTL and new trans mounts.

yea, they're probably not going to help much, My guess w/ the SSK was maybe shifter slop to worn bushings exacerbating the issue, but unlikely.

Sorry dude, the others are prob right...bad synchro. I too have heard of people having multiple tranny with issues.

[Mdriv3r]

Originally Posted by strokemycocktus

Since I have owned the car, I happen to have some issues with the second gear. The mileage is 60k kms.
It happens usually after hard acceleration on 1st. It doesn't matter on which rpm I try to shift - it sometimes happens on 4k and sometimes on redline. The gear grinds and locks. No problems on downshifts but I always rev match.
Shifting very gently and a bit slower makes the issue appear less frequently, but it still happens. I also get a slight grind on my first shift in the morning (very slow driving), but the gear eventually engages.
I have changed motor mounts and added F10 M5 knob, slight improvement but problem still occurs. The grind seems like shifting with clutch not fully in, but I am 100% sure it is every time.
I know some owners have reported synchro issues on this gearbox. Not sure if this is the case here, as the grind is clearly load related, not rpm. I am able to get smooth shifts on redline, it usually grinds on lower rpm after heavy acceleration.
My guesses are:
Clutch issue - air, or disengagement problem? It was replaced about 40k kms ago though and seems to be working fine overall.
Transmission mounts - engine mounts were done when replaced, so maybe these are too, and there is too much moment.
Excessive movement in the rest of the drivetrain - diff / rear subframe bushings, could this possibly cause some misalignment in the transmission?

Bottom line is I have a hard time to get repeatable smooth and fast shifts under heavy acceleration. Sometimes it goes great, and sometimes the gear grinds and I look like an ass on the road. I am going to flush the trans oil with redline MTL soon, but the it was already changed 25k kms ago so I don't expect night and day improvement.
Just to note, by shifting fast I don't mean smashing the shifter like a caveman
Any input will be much appreciated.

Try flushing the transmission fluid

[strokemycocktus]

Originally Posted by premo

Try flushing the transmission fluid

Yup, that's the plan - I getting redline MTL flushed next week and the transmission mounts changed.
BUT, I have noticed that some adjustments to my shifting with a weighted knob made everything better. So far I am getting nice smooth shifts near redline without even a crunch.
The synchros are probably a bit tired already, as to my understanding grinding should not occur under any circumstances (with the clutch 100% in of course), but being even more delicate with the shifter actually helps a lot and does not neccessairly make a shift slow.

I will report back after doing the work I mentioned, but so far I am rather happy with the way the car works. I had a moment I regretted not getting a dct, but it's already gone

[dparm]

I agree with what the others have already said in this thread: this is an internal problem and replacing parts and fluid likely won't do anything here. Likely a synchro that is starting to fail.

I'd start hunting around for a good local BMW shop since that transmission is going to need work soon. I wonder if there's replacement internal parts available in the aftermarket?

[strokemycocktus]

As mentioned above, no replacement parts are available. I will not replace the whole transmission when it seems to be working just fine with a little bit more care. The price i would need to pay is ridiculus, similar to (used) motor replacement in my country.
I believe the fluid will make it a bit better, which would do the thing for me.

[dparm]

Originally Posted by strokemycocktus

As mentioned above, no replacement parts are available. I will not replace the whole transmission when it seems to be working just fine with a little bit more care. The price i would need to pay is ridiculus, similar to (used) motor replacement in my country.
I believe the fluid will make it a bit better, which would do the thing for me.

I saw the post saying that ZF doesn't sell parts, but that doesn't mean the aftermarket hasn't stepped in to fill that gap.

However, I do understand and agree that the complexity of transmission repair is probably one of the most difficult things to do on a car, hence why people just replace the entire transmission. Maybe you can find a wrecked donor car.

[strokemycocktus]

Sorry, I missed that you mentioned aftermarket. I don't know about that so far, but it will be hard to find a shop that would be able to work on this transmission, since ZF does not provide any documentation.
There are a few used transmissions to buy, and when mine goes REALLY bad i will probably go this route. But so far it works just fine imo. Maybe I had some bad shifting habits with less precise transmissions and was using still excessive force while shifting.
This occassinal grinding does brother me from time to time, but as far as I feel that I can adapt to it and have fun nonetheless, I can definitely live with it

[motion732]

Sorry to semi-hijack but can grinding be confused with notchiness?

I experience notchiness between 2nd and 3rd only. Any when I say notchiness, i mean that the shifter goes in gear, but it kind of hits a point, resists briefly and then lands in gear. It's not always, I can't pinpoint when, but it does happen. Sometimes hard shifts are clean, sometimes there's a notch feel. Sometimes soft shifts are clean, sometimes there's a notch feeling.

I was thinking the approach of trans fluid / autosolutions SSK / shifter bushings to address it.

'08, e92, 65k miles. I like to think I don't need a new trans.

[Mdriv3r]

Originally Posted by strokemycocktus

Yup, that's the plan - I getting redline MTL flushed next week and the transmission mounts changed.
BUT, I have noticed that some adjustments to my shifting with a weighted knob made everything better. So far I am getting nice smooth shifts near redline without even a crunch.
The synchros are probably a bit tired already, as to my understanding grinding should not occur under any circumstances (with the clutch 100% in of course), but being even more delicate with the shifter actually helps a lot and does not neccessairly make a shift slow.

I will report back after doing the work I mentioned, but so far I am rather happy with the way the car works. I had a moment I regretted not getting a dct, but it's already gone

Good luck man. Synchro's could be your issue. I flushed mine with Redline MTL about 2.5 weeks ago. It made a fairly noticeable difference in shifting (smoother). I didn't have any snagging or grinding issues, but I do think that the trans flush is a step in the right direction.

Check out ECS tuning for parts.

[Ggeezer]

Originally Posted by motion732

Sorry to semi-hijack but can grinding be confused with notchiness?

I experience notchiness between 2nd and 3rd only. Any when I say notchiness, i mean that the shifter goes in gear, but it kind of hits a point, resists briefly and then lands in gear. It's not always, I can't pinpoint when, but it does happen. Sometimes hard shifts are clean, sometimes there's a notch feel. Sometimes soft shifts are clean, sometimes there's a notch feeling.

I was thinking the approach of trans fluid / autosolutions SSK / shifter bushings to address it.

'08, e92, 65k miles. I like to think I don't need a new trans.

Probably engine mounts if it's specifically limited to the 2-3 shift.

[strokemycocktus]

I was thinking, maybe I have a problem with clutch disengagement? It engages pretty low to the floor, and I always have a hard time putting the car into 1st gear, especially when rolling forward slowly (like 5-10 km/h).
Will try bleeding the system, is there anything else I could do? I had brake fluid changed about 6k km ago, used Motul RBF 660.
The car had a dealer visit at 21k km (62k currently) with a title Complete Clutch not opening. They have replaced the whole clutch and guide bush. Maybe there was something else that needed replacement?
Also there is audible rattle in neutral with the clutch released. Once I press it back in it immediately goes away.

[Taskmaster]

SO no one is going to comment on the OPs name? Hilarious!

[strokemycocktus]

Originally Posted by Taskmaster

SO no one is going to comment on the OPs name? Hilarious!

Hahaha thanks for noticing man