07-10-2014, 09:16 AM | #1 |
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2nd gear grind in manual transmission
When I accelerate briskly and shift into 2nd gear at around 5000-6000 rpm it sometimes grinds. It doesn't pop out of gear, it still engages though. I don't think this is normal. Does anybody else have this problem ?
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07-10-2014, 09:43 AM | #2 |
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Normal for 1st-2nd gear shift at higher RPMs. You will need to drop the RPMs a little more (more clutch in time) to get a smooth shift. High RPM shifts in lower gears can hurt the transmission in the long run. Try using 2nd-3rd shifts for higher RPM shifts for smoother action.
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07-10-2014, 10:27 AM | #3 |
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That's extremely disappointing that I have to granny-shift a car which allegedly has a manual transmission "borrowed from M3/M4" (quote from official BMW propaganda brochure).
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07-10-2014, 10:44 AM | #4 |
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Does make a weird power drillish sound and still go into gear? Or does it just grind and not go in? If its the first, you've got a bad syncro/transmission.
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07-10-2014, 11:05 AM | #6 | |
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Quote:
I hope its not the same situation for you. |
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07-10-2014, 11:19 AM | #7 |
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Thanks for the reply. I will test it today, depress clutch fully, wait one full second and then quickly shift so at least I know it is not clutch delay valve.
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07-10-2014, 11:20 AM | #8 |
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You can absolutely shift 1-2 at high RPM with no issues. You are either not pushing the clutch all the way in (or pulling down before its completely disengaged) or you have a bad synchro.
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07-10-2014, 11:32 AM | #9 |
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Some things to consider.
The synchromesh rings between first and second can be designed for more stresses / the first to second shift traditionally being the most abused or taking the most wear. You can actually shift too quickly, if you attempt to shift as fast as possible you can overwhelm the synchromesh and the second gear teeth. So there is a optimal speed of which to shift, don't slam but feel the meshing as you traverse the gearbox from first to second. It can still be quick but not nanosecond fast. Finally, try not grabbing the shifter with the palm of your hand vertical up against the right side of the shifter (left hand side configuration) but clasp the top of the shifter with the underside of your fingers and pull back with your distal phalanges and when pushing forward use the more carpal portion of you palm. But it could be a linkage issue. |
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07-10-2014, 12:12 PM | #10 |
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I need a degree in anatomy to understand this post.
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07-10-2014, 12:25 PM | #11 |
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mine doesn't grind, but the noise in 1-2nd gear is pretty notchy and clunky. does anyone have this issue? doesn't seem like the smoothest of transmissions
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07-10-2014, 12:30 PM | #12 |
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07-14-2014, 03:45 PM | #13 |
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Thanks for all the advise vis-a-vis driving smoothly. By the way I think it may be clutch problem, not synchros, because it grinds when I put it into second with the clutch still pressed. The synchros are not involved yet because they only start working later in the process (aka. after the clutch is released).
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07-14-2014, 03:56 PM | #14 |
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I do believe the syncromesh discs are used while clutch is depressed to floor and gear lever is sliding through from one gear to another - but I'm not questioning your diagnosis.
Actually a clutch repair is quicker and easier then a gearbox exchange. BMW dealer tech can probably find the cause in five-minutes. Very interested in how things develop, keep us posted. |
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07-14-2014, 08:23 PM | #15 |
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I am going to see the dealer tomorrow. I hope this is an isolated case and the gearbox can handle spirited driving for more than 3-months 4000km (that's how long I owned the car).
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07-15-2014, 09:10 AM | #16 |
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The foreman and I drove the car today and while he couldn't replicate the problem I could. I scheduled the next appointment on July 24th. Hopefully they will fix it then.
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07-15-2014, 11:48 AM | #17 |
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I shift mine very fast from 1-2 and have never heard any bad noises. You can have the foreman go with you while you drive too. If you can replicate the situation.
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08-05-2014, 02:59 PM | #18 |
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I just got a confirmation today the new transmission (pending BMW confirmation) will be arriving from Germany. I hope it was just a bad luck because you don't hear often about blown BMW manual transmissions.
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08-05-2014, 03:02 PM | #19 |
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Nice. Hopefully all will be resolved.
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09-12-2014, 04:00 PM | #20 |
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I had a new transmission put in yesterday. Just in time because the old one was grinding more and more and I worried it could disintegrate at any time. At least something good came out of it because I learned to start in 2nd gear smoothly so I could bypass the dreaded 1-2 gear grind (makes me cringe just thinking about it now).
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09-12-2014, 06:12 PM | #22 |
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Thanks, I will try. Clutch wasn't touched. I suppose you need to break the new gearbox in so I will ease off on those torque-intensive 1-2 and 2-1 shifts. I would also like to know what went wrong but I don't think BMW will admit they produced a shitty gearbox.
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