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    Difficulty Getting Into Gear at Speed

    Hey all,

    I was out around town today and noticed that I was having trouble getting the transmission into gear on downshifts. In particular, the issue seemed to be happening on downshifts at higher speeds (30mph+), but at a standstill I could row through the gears easily with the clutch disengaged.

    It seems to be happening across multiple gears, 6->5, 5->4, 4->3, etc., and when shifting it feels like it enters the gear halfway, then hits a resistance point where I'd normally feel it fully slot into gear. I can force it, or back out and re-enter, but there isn't the normal click and it feels sketchy. Otherwise there are no odd sounds, clutch engagement is normal (no slip or change in engagement point), no grinding. Transmission fluid was replaced 14k miles ago with MTF-1.

    Any ideas on where the issue might be stemming from? And is there a risk of blowing something up if I need to drive the car? Hoping that this is an issue somewhere in the linkage and not the transmission itself...
    '04 LSB Coupe 6MT
    All my money goes towards maintenance.

    #2
    Does your linkage feel fine? Any play in the shifter (in all three dimensions, not just front-back or left-right)? Did your shifter carrier bushing pop out of place? Any other drivetrain clunks or noises that may point towards failed rubber? Do you have a clutch stop? Have you messed with the brake/clutch lines recently? Has the outside temp dropped where you live?

    Sorry for the million questions, but your issue could be caused by many things. However, I doubt this is due to some spontaneous transmission failure. Probably something failed/became loose in your shifter linkage or drivetrain.
    2002 Topasblau M3 - Coupe - 6MT - Karbonius CSL Airbox - MSS54HP Conversion - Kassel MAP - SSV1 - HJS - PCS Tune - Beisan - MK60 Swap - ZCP Rack - Nogaros - AutoSolutions - 996 Brembos - Slon - CMP - VinceBar - Koni - Eibach - BlueBus - Journal

    2012 Alpinweiss 128i - Coupe - 6AT - Slicktop - Manual Seats - Daily - Journal

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      #3
      I would start by bleeding the clutch and changing the trans oil, cheap and easy.

      Comment


        #4
        Originally posted by heinzboehmer View Post
        Does your linkage feel fine? Any play in the shifter (in all three dimensions, not just front-back or left-right)? Did your shifter carrier bushing pop out of place? Any other drivetrain clunks or noises that may point towards failed rubber? Do you have a clutch stop? Have you messed with the brake/clutch lines recently? Has the outside temp dropped where you live?

        Sorry for the million questions, but your issue could be caused by many things. However, I doubt this is due to some spontaneous transmission failure. Probably something failed/became loose in your shifter linkage or drivetrain.
        Thanks, this is really helpful to think things through. The linkage feels fine just rowing at a stop, but something is getting in the way at speed, so if it is the linkage then perhaps it's the connection / bushings that mate to the transmission. No extra play in the shifter, or new clunks or noises outside of M clunks that I've gotten used to. I don't have a clutch stop, and being fully depressed on downshifts doesn't change anything, nor have I done any brake / clutch line work recently. Temps have fluctuated in LA, but only from hot 90+ to around 80F, so no cold exposure.

        One of the bushings failing seems likely based on how it feels, if it means that there would be some kind of broken rubber that's getting in the way of the engagement. I've been planning the shifter refresh anyways, so it might be time to get in there and just get it done. At 175k miles I've been slowly replacing every single rubber part in the car as of late 😂.

        Originally posted by beefaroni View Post
        I would start by bleeding the clutch and changing the trans oil, cheap and easy.
        While I initially thought this too, everything on the clutch side / engagement feels pretty normal, it's more something blocking it getting into gear. I'll start with the linkage and then investigate the clutch / tranny if I don't find anything.
        '04 LSB Coupe 6MT
        All my money goes towards maintenance.

        Comment


          #5
          Originally posted by dukeofchen View Post
          At 175k miles I've been slowly replacing every single rubber part in the car as of late 😂.
          If your linkage bushings are original at that mileage then yeah definitely start there.
          2002 Topasblau M3 - Coupe - 6MT - Karbonius CSL Airbox - MSS54HP Conversion - Kassel MAP - SSV1 - HJS - PCS Tune - Beisan - MK60 Swap - ZCP Rack - Nogaros - AutoSolutions - 996 Brembos - Slon - CMP - VinceBar - Koni - Eibach - BlueBus - Journal

          2012 Alpinweiss 128i - Coupe - 6AT - Slicktop - Manual Seats - Daily - Journal

          Comment


            #6
            Quick update to this situation which I haven't gotten to the bottom of yet.

            I got under the car and did a full refresh of the shift lever, cup bearing, and all bushings in the linkage including the carrier bushing. While I was there I discovered that both transmission mounts had completely sheared, so I threw in the Rogue mounts that I also had laying around as well. The gear linkage feels much tighter and crisper now, but the problem shifting getting in and out of gear still persists.

            Originally I had suspected that some slack or flex in the drivetrain was messing with the alignment of the shifter linkage, but at this point with motor mounts replaced in the last 10k miles, tranny fluid 15k miles ago, and now all shifter and transmission mounts as well, it seems like I can rule that out. Which would leave either a hydraulic issue or the clutch itself.

            As time goes on I have noticed more difficulty getting out of gear, as well as some grinding when it's being particularly difficult about getting into gear, so I might not be getting full disengagement after all. Next up will be checking fluid levels and inspecting and bleeding the master / slave cylinders for leaks. Pedal feel isn't terrible and engagement point isn't completely out of whack but I'm not sure I trust myself to know for sure if the issue has been slowly creeping up. I haven't noticed any slippage or odd sounds when releasing the clutch, so pressure plate / throw out bearing seems like a decent possibility if it is in the transmission itself.

            Any flaws in this reasoning or something I might be overlooking?
            Last edited by dukeofchen; 12-24-2020, 03:55 PM.
            '04 LSB Coupe 6MT
            All my money goes towards maintenance.

            Comment


              #7
              Originally posted by dukeofchen View Post
              As time goes on I have noticed more difficulty getting out of gear, as well as some grinding when it's being particularly difficult about getting into gear, so I might not be getting full disengagement after all. Next up will be checking fluid levels and inspecting and bleeding the master / slave cylinders for leaks. Pedal feel isn't terrible and engagement point isn't completely out of whack but I'm not sure I trust myself to know for sure if the issue has been slowly creeping up. I haven't noticed any slippage or odd sounds when releasing the clutch, so pressure plate / throw out bearing seems like a decent possibility if it is in the transmission itself.

              Any flaws in this reasoning or something I might be overlooking?
              The bolted texts seem to be correct logic. However you didn't say the problem happened when shifting to R or 1st from stopped car. I would expect a "start to come apart" bad clutch would cause the R and 1st shifting as said. If R and 1st shifting have no issue then it's not master/slave or air in fluid issue as the clutch was disengaged fully. If nothing else to check then I agree that time to look/replace the clutch.

              Comment


                #8
                Originally posted by sapote View Post

                The bolted texts seem to be correct logic. However you didn't say the problem happened when shifting to R or 1st from stopped car. I would expect a "start to come apart" bad clutch would cause the R and 1st shifting as said. If R and 1st shifting have no issue then it's not master/slave or air in fluid issue as the clutch was disengaged fully. If nothing else to check then I agree that time to look/replace the clutch.
                Makes sense, I don't have issues getting into R or 1st from a stop. Instead it seems to become progressively worse above 3k RPM, so I've been trying to figure out exactly where that association would come into play within the system. Thinking about it more I agree that it doesn't seem to match up with a hydraulic issue that would affect things irrespective of speed / load.

                Was hoping this would be DIY-able but if it's moving in the direction of the clutch then it might be time to give the shop a call on this one.
                '04 LSB Coupe 6MT
                All my money goes towards maintenance.

                Comment


                  #9
                  Circling back many months later as I still haven't gotten to the bottom of this. Luckily I haven't had to drive much since COVID, but the problem is still there and seems to have gotten worse over time even with light driving.

                  On a hunch I swapped one of the transmission compression springs (discussion here) that has a tendency to snap in SMGs, manifesting as the SMG having trouble finding gears. The new one was slightly thicker than the old one, but my original was in fine condition. Also did a full fluid flush (brakes and clutch) last week just to be sure, and didn't notice any low fluid levels or obvious leaks in the slave cylinder while I was in there. Clutch pedal feels better, but the same "lockout" behavior is there.

                  When the car was in for rod bearings my mechanic suggested it was time for a new clutch assembly, based on the mushy pedal feel and substantial notchiness going into first / reverse gear. I'm inclined to trust these guys based on my previous experience with them, even though the symptoms don't seem to be your typical clutch issues (this is my first MT car).

                  I've bit the bullet and gathered all the parts for a clutch / flywheel job which I will attempt to undertake myself over the coming days. As far as this specific issue goes, my best guess right now would be damage or wear in the release mechanism (clutch fork / pin, TOB, pressure plate) that is preventing full clutch disengagement, causing the resistance / grinding when attempting to enter the next gear.

                  Figured I'd bump as an update for posterity, and potentially get any last minute ideas of things to check before I dive in. Money is tight right now and I hate to be throwing parts at the car, but at this point it seems like I've run through the process of elimination.
                  Last edited by dukeofchen; 08-02-2021, 12:36 PM.
                  '04 LSB Coupe 6MT
                  All my money goes towards maintenance.

                  Comment


                    #10
                    Originally posted by dukeofchen View Post
                    Figured I'd bump as an update, and potentially get any last minute ideas of things to check before I dive in. Money is tight right now and I hate be throwing parts at the car, but process of elimination seems to have led to this.
                    I think this is sound logic and I don't think you'll get any alternative ideas at this stage. Good luck
                    '05 M3 Convertible 6MT, CB/Cinnamon, CSL Airbox&Flap, PCSTuning, Beisan, Schrick 288/280, SS V1's & 2.5" System, RE Stg 1&SMF, KW V2, CB PS, Apex EC-7R

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                      #11
                      You might check for a worn shifter bushing.


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                        #12
                        Originally posted by jbfrancis3 View Post

                        I think this is sound logic and I don't think you'll get any alternative ideas at this stage. Good luck
                        Thanks! I'm taking pictures and will put together a guide of sorts for inexperienced DIY'ers like myself. Haven't been able to find an M3 specific one yet that isn't a graveyard of dead images.

                        Originally posted by Estoril View Post
                        You might check for a worn shifter bushing.
                        This was actually one of my first stops in troubleshooting this issue, so the shift lever, cup, bushings and pins will all be crispy once this is sorted.

                        '04 LSB Coupe 6MT
                        All my money goes towards maintenance.

                        Comment


                          #13
                          I re-read your posts and thinking about this: the shifting resistance is more defined at around 4000 rpm. Since this is your first MT, do you try double-clutch or rev matching (bleeping the gas pedal) when down shift? Too much gear speed differential could lead to fast synchro wear out then having the same symptom as you described.

                          Have you tried this suggestion -- in your other thread -- to see if the clutch is dragging "This can be checked easy on a slope driveway or road: engage 1st or R then press down clutch pedal slowly until car starts rolling, then notice how much more the pedal can go down before hitting stopper. It should have enough free travel" ?

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                            #14
                            Long shot, but are all the bolts tight, trans to engine, etc.
                            2004 M3 Mystic Blue

                            Comment


                              #15
                              Originally posted by sapote View Post
                              I re-read your posts and thinking about this: the shifting resistance is more defined at around 4000 rpm. Since this is your first MT, do you try double-clutch or rev matching (bleeping the gas pedal) when down shift? Too much gear speed differential could lead to fast synchro wear out then having the same symptom as you described.

                              Have you tried this suggestion -- in your other thread -- to see if the clutch is dragging "This can be checked easy on a slope driveway or road: engage 1st or R then press down clutch pedal slowly until car starts rolling, then notice how much more the pedal can go down before hitting stopper. It should have enough free travel" ?
                              During my time of ownership at least (the last 45k out of 180k miles) I've always rev matched on downshifts. Perhaps a little sloppily as I was learning at the beginning, but I rarely if ever fully allowed the transmission to pick up any speed differential. Can't attest to the previous 2 owners though – would be a huge bummer if this ended up being a synchro issue in the end. If it were a synchro issue, would it present across all gears, or be localized to specific gears / gear changes? Because at this point just about any shift above that RPM threshold will produce the issue.

                              I forgot to try that exact clutch drag test, might throw the exhaust / tranny brace back on tonight and give it a go. Just to be sure, the test would be (1) clutch all the way down, put into 1st or R (2) release clutch until it reaches lowest engagement point (3) evaluating the distance between the lowest engagement point and fully down, and if that distance is very small that points to clutch drag?

                              Just did some searching and it looks like another similar test would be to put the car in 1st with the clutch fully down, then give it some revs and see if the car moves at all. I'll try both when I have a chance.
                              Last edited by dukeofchen; 08-02-2021, 03:32 PM.
                              '04 LSB Coupe 6MT
                              All my money goes towards maintenance.

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