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My car seems to have developed a problem tonight with the 2nd gear. Some times it is almost impossible to get it into gear, it does not grind or anything, just feels when you try to change gear when the clutch isn't pushed in. It happens on and off and mainly affects the 2nd gear, but did it once or twice in the 1st as well. When it is good, it changes without any issues, but when it is playing up, its almost impossible to change to 2nd. Could it be the slave? I have yet to check the fluid level. Any input will be greatly appreciated. Thanks guys.

My car seems to have developed a problem tonight with the 2nd gear. Some times it is almost impossible to get it into gear, it does not grind or anything, just feels when you try to change gear when the clutch isn't pushed in. It happens on and off and mainly affects the 2nd gear, but did it once or twice in the 1st as well. When it is good, it changes without any issues, but when it is playing up, its almost impossible to change to 2nd. Could it be the slave? I have yet to check the fluid level. Any input will be greatly appreciated. Thanks guys.

So you took the time to post a question here and you haven't bothered to take the time to check the fluid level?

I think you know what you need to do first.

Line clamp the clutch flexible hose and then press on the clutch pedal with medium effort. If the pedal slowly sinks away, then you have a hydraulic problem with the master cylinder.

Peel back the boot on the slave cylinder and make sure it doesn't piss fluid out.

Once you have checked that, get someone to check the operation of the pushrod.

Then check oil level in the gearbox

If all those come back good, then it is a synchro problem

Alright, just ordered nismo operating cylinder and braided line just in case. Hopefully that'll fix the problem.

Thanks heaps for the help Elite Racing, it is much appreciated. :-)

This is 95% a synchro / synchro hub problem as clutch issues usually give you grinds not jams/lockouts. Also, you tend to experience the same problem in all gears not just one or two. Slave cylinder may eventually need replacing but given you had no major loss of fluid you've just wasted some cash IMO.

This is 95% a synchro / synchro hub problem as clutch issues usually give you grinds not jams/lockouts. Also, you tend to experience the same problem in all gears not just one or two. Slave cylinder may eventually need replacing but given you had no major loss of fluid you've just wasted some cash IMO.

Not entirely true.

When you have a hydraulic problem in the clutch system and it has not hydraulically failed but is lacking in pressure holding ability, the most worn synchro in the gearbox is usually the more noticeable.

It does not mean the synchro is fubar completely, it just means it is more critical of a perfect working environment.

It is also not a waste of money considering it is currently his cheapest option to try and the slave is leaking so it needs to be replaced anyway. If there is a certain problem in front of you, you correct it before moving on. Sometimes it may be the whole problem, other times its part of a bigger one.

He also stated the inconsistent nature of the problem in his first post which led me to believe it could possibly be something other than a synchro. As usually synchros are always worn, the dont normally come good for a few days, then go back again. Hydraulic cylinders can do this.

It happens on and off and mainly affects the 2nd gear, but did it once or twice in the 1st as well. When it is good, it changes without any issues, but when it is playing up, its almost impossible to change to 2nd.

Synchros can be inconsistent, all it takes is the difference between matching revs fine and not, e.g. not compensating for travelling up a hill. Also, gearbox oil viscosity as a result of temperature can make synchro wear symptoms inconsistent. The fact he hasn't noted anything about other gears doing it suggests this to me...because if a clutch take up point is too low to the floor as a result of too little pressure then you will definitely feel some sort of changing issue in other gears. Then we have the 2nd gear synchro theory - being most frequently replaced and problematic synchro...as per the frequent use and the fast changes and the gearing down and the soon to be empty wallet.

The fact his fluid was full suggests it isn't a major leak in the slave cylinder - if we adopted the "replace every problem you see in a car" mentality then we would all be dirt poor. Most people don't have money to throw at their cars and will only replace something when it is a necessity to do so. Yes it's the cheaper of the two solutions but he should have done more diagnosis on this before forking out for another one. That said, my theory gets shat on because if he's ordering parts after a couple of posts then maybe he does have money to burn...

Synchros can be inconsistent, all it takes is the difference between matching revs fine and not, e.g. not compensating for travelling up a hill. Also, gearbox oil viscosity as a result of temperature can make synchro wear symptoms inconsistent. The fact he hasn't noted anything about other gears doing it suggests this to me...because if a clutch take up point is too low to the floor as a result of too little pressure then you will definitely feel some sort of changing issue in other gears. Then we have the 2nd gear synchro theory - being most frequently replaced and problematic synchro...as per the frequent use and the fast changes and the gearing down and the soon to be empty wallet.

The fact his fluid was full suggests it isn't a major leak in the slave cylinder - if we adopted the "replace every problem you see in a car" mentality then we would all be dirt poor. Most people don't have money to throw at their cars and will only replace something when it is a necessity to do so. Yes it's the cheaper of the two solutions but he should have done more diagnosis on this before forking out for another one. That said, my theory gets shat on because if he's ordering parts after a couple of posts then maybe he does have money to burn...

Yes you are right, synchros are probably going to be the problem here but like I said, considering we have a confirmed failure of a part that has a lot to do with how the gearbox will engage gears, it is more practical to replace the known failed part before proceeding further. I think you would agree that if he went out and rebuilt the gearbox, only to find it was a simple solution, that he would be quite upset.

It's not a matter of 'replace every problem you see in a car' but moreso assessing the condition and judging whether there are simple resolutions before embarking on an expensive gearbox rebuild.

Even if it ends up being synchros, at least when the gearbox is rebuilt, he will have a 100% correctly functioning hydraulic system. New slave cylinders are only $100. Big bore was not necessary and neither was the clutch line, but then again, no one told him to go out and buy anything either.

thanks guys for the knowledge on the subject. I'm leaning towards Elite Racing's judgement since the box was working pretty much 100% without any grinding or difficulties getting into any of the gear. It just happened out of the blue the other night and the problem was on and off. Out of the 50 times I changed gear that night, it probabaly only played up 8 times. Doesn't crunch or anything, just can't pull it, like th clutch is not pushed in or somthing. Pedal felt slightly lighter too, I forgot to mention, but it wasn't very noticable. The clutch fluid did go down slightly every month, so this is probabaly explained by the leaky slave, which looked fine on the outside with no oil stain or anything, until I peeled back the dust boot.

Hopefully the new parts will fix up the problem. God I hope its not anything else.

Edited by __PhaseShiftDown
thanks guys for the knowledge on the subject. I'm leaning towards Elite Racing's judgement since the box was working pretty much 100% without any grinding or difficulties getting into any of the gear. It just happened out of the blue the other night and the problem was on and off. Out of the 50 times I changed gear that night, it probabaly only played up 8 times. Doesn't crunch or anything, just can't pull it, like th clutch is not pushed in or somthing. Pedal felt slightly lighter too, I forgot to mention, but it wasn't very noticable. The clutch fluid did go down slightly every month, so this is probabaly explained by the leaky slave, which looked fine on the outside with no oil stain or anything, until I peeled back the dust boot.

Hopefully the new parts will fix up the problem. God I hope its not anything else.

Well that's a bit of new information right there...if you are losing fluid and noticing a difference in the clutch pedal then I will side with ER's theory. Be interesting to see the results, please let us know how you go.

Worst case scenario if your slave cylinder repair doesn't fix it then you will need to reco your gearbox...bout $1000-$1300 worth.

  • 1 month later...

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