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Discussion Starter #1
Hi, I have searched, but could find nothing like this. A couple of hours ago i was giving it some around some beatiful tight curves stringed together by straights of no more than a few hundred yards. 2nd gear corners, around 40mph, up into 3rd on the straights, then back into 2nd. I consider myself to be quite good at heel and toe and was doing this for the whole journey, whether pushing or not, just to get a bit more practise in! Anyway after a while, maybe the 5th bend or so, coming into the tightest bend, I could not select 2nd on the downchange:mad:, double de-clutched, still nothing, selected third and floored it to the next corner, same thing again. 3rd to the next bend this time it went in, though it was a struggle.

i believe the clutch is quite new, maybe done 5000 miles, and the diff and gearbox oils were done at the smae time. This has only happened to me today but its the first time i've pushed it this hard it has to be said!!!

Any ideas??? Thanks:biggrinbounce:





Lee
 

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This probably isn't the same problem, but I've always found my 3rd to 2nd downshift to be the hardest and slowest. Shifting up from 2nd to 3rd is no problem, but going from 3rd to 2nd just isn't smooth. I can't really do it in a straight line like the upshift. I find myself having to take it straight out of third, go over to the left, and then down into second. Here's a simple diagram that might help explain:

 

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Sounds like your syncro hubs have gone on second gear, these slow and match gear speeds.

Did you get any bulking before your spirited drive?

Change the gearbox oil, do it in a clean white or clear tub and look for metal filings or the fluid looking like metalic silver paint, if so thats your answer and a box swop or rebuild will be on the cards.

Jay
 

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Discussion Starter #4
This probably isn't the same problem, but I've always found my 3rd to 2nd downshift to be the hardest and slowest. Shifting up from 2nd to 3rd is no problem, but going from 3rd to 2nd just isn't smooth. I can't really do it in a straight line like the upshift. I find myself having to take it straight out of third, go over to the left, and then down into second. Here's a simple diagram that might help explain:

Yeah as you said its not that, i understand what your saying though, but from 2nd to 3rd it is sprung across so you can push through to 3rd in a seemingly straight line, but on the way from 3rd to 2nd, you have to overcome the springing action, so it is not as smooth, but thanks anyway, nice diagram!:S
 

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Discussion Starter #5
Sounds like your syncro hubs have gone on second gear, these slow and match gear speeds.

Did you get any bulking before your spirited drive?

Change the gearbox oil, do it in a clean white or clear tub and look for metal filings or the fluid looking like metalic silver paint, if so thats your answer and a box swop or rebuild will be on the cards.

Jay
I was fearing something like that! Sounds expensive to me! It's not affecting me too much at the mo so is it a necessity to do it before it does anymore damage or is it ok for now??


Lee
 

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I was fearing something like that! Sounds expensive to me! It's not affecting me too much at the mo so is it a necessity to do it before it does anymore damage or is it ok for now??


Lee
Well, if the synchros are gone, I don't think you can hurt them further. Gear oil change is cheap and may help. You may also want to check the linkage and shifter bushings to make sure all is good. If you can't get it into gear even rev matching, i would suspect something other than synchros. If the bushings are worn, or the linkage is out of adjustment, you are not getting the gears to correctly line up.

Try it with engine off and gently move the gear lever up and down, 2-3 and 3-2. Synchros are out of the equation with engine off.

Regards,
Jerry
 

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I'm not sure if this will help, but I had a somewhat similar experience and installed a DSSR. That helped my shifting and no problems ever since...
 

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Do you have the UUC DSSR? Perhaps that is causing part of the problem. Some people had issues going into second gear. Very few did though. If thats not it, it coudl be synchro related. Possibly a worn synchro/baulk ring. Cha

What fluid was put into the tranny? That could be part of the issue.
 

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Discussion Starter #9
I'm not sure if this will help, but I had a somewhat similar experience and installed a DSSR. That helped my shifting and no problems ever since...
i don't think its that but thanks:M5thumbs:
 

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Discussion Starter #10
Do you have the UUC DSSR? Perhaps that is causing part of the problem. Some people had issues going into second gear. Very few did though. If thats not it, it coudl be synchro related. Possibly a worn synchro/baulk ring. Cha

What fluid was put into the tranny? That could be part of the issue.
i don't have uuc dssr so thats not it. PO was a very maticulous (is that how you spell it??lol) guy, had everything done to it on 126,000, it's now on 129,000. Service sheet comes to £1650 ($2750!!) part of that was diff and gearbox oil but doesn't say which was used!

Lee
 

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I think the problem may be that you are overshooting the 1-2 gate and going into the reverse gate. This is surprisingly easy to do esp. when you're driving hard. I'm betting that is what's happening.
 

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Perhaps the PO noted the same problem as you did and replaced the transmission oil as a band aid fix in hoping it would fix it, but now the problem is starting to happen again. Im not too sure, but if it was taken to a BMW dealership it should have the LTF-2 fluid in it or whatever the updated version of the lifetime fill fluid is.

Perhaps try switching to Royal Purple Synchromax ive heard only positive reviews and for a lot of people it helps the crunchiness going into 2nd gear especially when cold!
 

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Discussion Starter #13
Perhaps the PO noted the same problem as you did and replaced the transmission oil as a band aid fix in hoping it would fix it, but now the problem is starting to happen again. Im not too sure, but if it was taken to a BMW dealership it should have the LTF-2 fluid in it or whatever the updated version of the lifetime fill fluid is.

Perhaps try switching to Royal Purple Synchromax ive heard only positive reviews and for a lot of people it helps the crunchiness going into 2nd gear especially when cold!
Thanks I'll try it on my inspection 1 next time its in. the big service on 126k was done at an indy, it hasn't done it again so i'm not sure really, maybe i done as beastmw said but i wouldn't of thought so! Stranger things have happened tho! cheers guys
 
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