2016 M3 6MT 4th gear grinding feeling?

[climachy]

Guys,

So I've got a brand new 2016 M3 6MT currently with 1300 miles but from day one I noticed a weird grinding or rubbing feeling sometimes in 4th gear. After testing things a bit I have come up with the scenario which will cause it to happen most consistently.

When downshifting into 4th gear at 4-5k RPMS once in 4th gear, with rev matching off (engaging one of my M buttons) I get this grinding/reverberating/weird sensation I feel through the shifter and can hear as I pull off the clutch. It's usually when I'm not doing much rev matching myself but letting a little slower let off of the clutch allow for a smoother transition. If I rev match it myself well, it doesn't usually cause this problem. I've been driving stick for 11 years on BMWs so I know how to use them and how they feel. This also has only happened in 4th gear while I use the same shifting strategies in all gears on downshifting. I haven't done my break in service (soon to be done) or my rear differential recall (will be done at break in visit) yet. I'm obviously going to tell the dealer but anybody have an idea what this is? I always wondered if I wasn't seating it into 4th gear and it was trying to slip out but I've pushed it pretty strongly into 4th and it can still happen. The fact that it's somewhat intermittent is also annoying ... specifically what conditions are causing this? Any thoughts? Big deal, little deal?

Any insight would be great!

Thanks guys ahead of time!

[Someone?]

Take it right back to the Stealership

[Draper]

I feel like I've noticed this once or twice, though didn't really pay attention to the circumstances - just a mentally noted it was odd.

Will pay more attention based on your description though.

[literbikes]

Does it do it without rev matching off in sport+? Definitely take it to dealer though. Good luck.

[climachy]

Originally Posted by literbikes

Does it do it without rev matching off in sport+? Definitely take it to dealer though. Good luck.

Hmmmm, I thought rev matching was always off in sport+. I guess I would have to try that. Does that mean something if it does do it with rev matching on in sport+?

And I wanted to make sure I was clear. It doesn't grind or anything while I'm putting it in gear, it grinds while I'm taking my foot off the clutch.

Thanks!

[climachy]

Originally Posted by Draper

I feel like I've noticed this once or twice, though didn't really pay attention to the circumstances - just a mentally noted it was odd.

Will pay more attention based on your description though.

Yeah that's exactly what was happening at the beginning I was like 'wait did that just happen?' And then I would push the clutch back down and release again and sure enough it kept doing it during that shift. I just had to ignore it and release the clutch and move on. Let me know if you do notice it!

[shiv.nandak]

Does it rub even after the oil warms up? I used to have some rubbing in 3rd gear after a cold start, but that went away after the transmission broke in a bit more. As i understand, the transmission takes 7-10k miles to fully break in.

[amw896]

I have a 235 but I found when it was new it was really notchy and a bit inconsistent in engagement. I tried double clutching as often as I could for the first couple months and now it shifts like butter. Only once warmed up of course.

[Harveyd396]

i posted this back in july

Please do this test- 6th gear 50-60 mph, do not touch the gas pedal, decelerating. Push the clutch pedal in and out slowly, at the friction point hold the pedal in that spot and listen for a grinding noise and vibration in the gear shift lever. Try this a few times before you decelerate below 40 mph. This may also happen in 4th gear, not as bad. My dealer has replaced my clutch assembly and complete transmission, still does it. This maybe something we can live with or not. You may have this problem and never noticed it before doing this procedure to discover it. Please report your findings to this thread, could be a major issue.


"It all started when I went to my dealer for an oil change. The service rep drove my car into the service bay and came back to with his take on a potential clutch problem. Since I never drove another M car with a manual trans I couldn't dispute his diagnoses that my clutch pedal was grabbing too high and there was not enough pressure, the clutch pedal was too easy to push. They replaced the pressure plate which contains a clutch plate inside and the outer clutch plate, thus the dual clutch assembly was changed under warranty. They said my original pressure plate was defective from day one. I did notice the clutch did feel different and seemed to be improved."

I will have to explain this clutch problem in the finest detail for it to make sense. I have owned my M3 for 6 months and have 12,000 miles on it. During this time I did not have any problem with the clutch or transmission. If it did this vibration or noise I would have noticed it immediately, I have been driving manual high performance cars for 45 years. It all started when I went to my dealer for an oil change. The service rep drove my car into the service bay and came back to with his take on a potential clutch problem. Since I never drove another M car with a manual trans I couldn't dispute his diagnoses that my clutch pedal was grabbing too high and there was not enough pressure, the clutch pedal was too easy to push. They replaced the pressure plate which contains a clutch plate inside and the outer clutch plate, thus the dual clutch assembly was changed under warranty. They said my original pressure plate was defective from day one. I did notice the clutch did feel different and seemed to be improved. It didn't take 1 day for me to notice something going on that was not right. I heard a strange noise when the clutch was cold upshifting normally going into fifth gear. Then when releasing the clutch going into sixth I heard this infamous noise and felt a vibration in the gear shift lever. Of course I don't normally play with the clutch pedal trying to hold the friction point just to prove this noise exists. This problem NEVER happened with the original clutch assembly. I could live with it the way it is, it's just that it shouldn't be there! My dealer thinks it is the transmission, so now I have a new one, thank you BMW for a unnecessary gift. I am concerned for one reason, I own this car, not leased and I plan on keeping it for many years, it is the perfect car. I am afraid that after the warranty is finished there could be a real problem here that could show up and cost many thousands to fix. I would like to get it right now on BMW's tab.

Recent update, have 16,000 miles now, noise still there if I make it happen. I am sure every M3/4 has this problem if you know how to find it, It's normal, ignore it.

[Bunyfofu69]

I'm having this very same issue in 4th gear. Slowly letting the clutch out. Get a slight grinding sound, up until 3k or so. But when I put gas on it, it goes away.

Tried it in every gear. Only hearing it in 4th while rolling 30-40mph.

I have 320 miles on my 2016 6MT. Will take it into the dealer.

[M-Pilot]

Originally Posted by climachy

Hmmmm, I thought rev matching was always off in sport+. I guess I would have to try that. Does that mean something if it does do it with rev matching on in sport+?

And I wanted to make sure I was clear. It doesn't grind or anything while I'm putting it in gear, it grinds while I'm taking my foot off the clutch.

Thanks!

Rev matching is always off in Sport+.

[Dumpspec]

i also have a similar issue with my M4. once in a while it's hard to go into 4th sometimes. Even after i installed my short shifter it still happens.

[climachy]

I think Harvey's post is very useful. I actually don't seem to have the problem anymore. I now have about 2600 miles on my 2016 M3 and I had the rear diff service along with the break in service and I didn't notice it after. Might be coincidence, might be since it's intermittent the right conditions aren't there. Once Harvey wrote that he's basically changed everything and it didn't change I decided to take his advice and ignore it if it happens again.

[M Vier]

Thanks for the post. It's reassuring.

I was so happy with how reliable and practical my M4 is, until I heard this grinding noise. I was screaming in my head "please go away".

Now, my car's odo reads 35K miles. Similar to all of you, I get this noise when I'm shifting to 4th and 6th gears on sport + if I let the rpm drop then release the clutch slowly.

I guess I'll take your advise and just live with it.

[denemante]

I know this thread is 5+ years old now, but I'm hoping someone is still around. I have a 2015 M4 F82 with 33K miles and manual transmission. I've put about 1000 miles on it, and it's fantastic. A few weeks ago, I heard this bizarre sound from the rear end every time I revved to 3000 RPMs. It was high pitched like a piece of metal vibrating in the wind. Took it in, and was told it was the clutch. They admitted this was strange because these things are tanks, but it was replaced.

I've gone easy on it since I got it back to work the new clutch in. Then I noticed that when downshifting into 4th gear, there is a slight grind as others have noted here about 4th gear. I could only produce this once when upshifting and it was barely there. But it happens every time when downshifting into 4th.

I've noticed that this only happens in Sport Plus, not the other two modes.

This problem wasn't there before I had the clutch replaced - but the trans and clutch are two different things, so not sure how one might affect the other.

Did anyone ever figure out this 4th gear deal? I can't remember which mode rev-matching is in, but figure this issue may be computer related because it only happens in Sport Plus. Thoughts?

[Baron_Thunderbottom]

I've only had my 2014 M4 a month but its done this downshift grinding a couple of times into 4th. I was so relieved to find this post, as the originator states, it only seems to do it if you don't manually rev match. Comfort and Sport modes rev match for you, hope this helps, I'm just happy this is normal and mine isn't broken.