Help Needed! - Clutch Or Gearbox Issue?

[Jenius]

I dunno if anyone has been having his problem but recently the gearbox has been getting annoyingly difficult to shift.

especially in the case when I attempt to shift slightly faster than normal between 1st-2nd and 3rd-4th. This is for an R32 GTS-t.

its as if when shifting from 1st to 2nd it doesn't crunch but it can't find the slot for 2nd. I have to shift like really slow for it to slot in nicely. I'm running an OS Giken button clutch thats a 5-puck I think and its pretty heavy on the feel. (it came with the car when I bought it so its been on the car for about 5 years now.)

I also have to issue sometimes when slowing down to stop at traffic lights and moving at low-speeds in the carpark when I press the clutch and brake to slow down to stop and try to slot it in neutral it gets stuck in gear and I have difficulty pulling it into neutral. There's been scary moments where I've had to fight to stop the car at the lights cos its still in gear and keeps wanting to move forward!!

The clutch is still running fine and and doesn't slip and I had to replace the Clutch Slave Cylinder (the one thats located next the to gearbox housing under the car) as it was leaking and I had to drive a day without any fluid in the reserviour.

Would I need to also replace the Primary Clutch Cylinder too?

Any ideas or suggestions would be greatly appreciated! I just hope its nothing too serious where a simple oil-change would help.

[Abo Bob]

Try bleeding the clutch system for a start. Sounds like it's not disengaging properly.

[Trav33]

I noticed my clutch showed a similar sympton.

I couldnt skip gears from 2->4 or 3->5 until the revs dropped a bit.

I've now had my clutch replaced, and dont have this problem. I suspect ur problem is not gearbox related, but clutch.

[Green_s13]

sounds like clutch, i would get the system re-bleed, also th slave cyclinder did you replace it with a nissan one??

[Jenius]

Yeah the clutch was the issue.

I had a mechanic friend look at it for me and we determined that the Clutch Master Cylinder was on its way out and that it also needed a gearbox oil change.

I replaced the Slave Cylinder with the geniune Nissan item and now I've purchased a Primary one from the Nissan Essendon dealership.

They were really helpful and fast on the delivery, ordered it in the morning and picked it up by the afternoon.

all up the Primary Cylinder only cost me $108 and the Slave was about $90.

Will be installing it today so see how things go.

Thanks I was worried the synchro was gone or something.

[skylinegtts]

how did u go?

did u install it urself? how difficult was it?

[Jenius]

Yeah my old man decided to install it one day when I was at work and he found it too difficult to do.

So he ended up taking it to a mechanic friend of his and installed it within an hour.

Been driving around with it for a bit and its still having the issue although not as much.

I've also bought some Castrol Syntrans gearbox oil as I don't think the oil has been changed in the last 4 years. and its been through 4 track days so far. So most likely it could be the issue.

worse case scenario would be that my gearbox is basically F@%k'd and I'll be needing a new one. although its not crunching at all though.

hmm it might also just be the pressure plate. a lot of my friends who've driven it generally complain how heavy the clutch feels. oh wellz

[FATGTS-R]

Have you noticed any change with the pedal height?

You mention a very heavy clutch and I also have a heavy clutch and had the exact same scenario one time.

The problem was a mangled clutch pedal box/bracket. Its only made from thin folded metal with a random tack weld here and there. A heavy clutch can bend and twist up this bracket so when your pressing the pedal down to disengage a lot of the travel is lost with the bracket bending and not the clutch fork moving.

If your on your own get underneath the dash with a torch and have a look or get a mate and get him to press the clutch down while your underneath the car and looking at the travel to see if it coincides with the pedal movement.

Long shot I know, but it pissed me off for a while trying to find the problem and is also a common problem when heavier clutches are fited.

[Cubes]

$108 for the Genuine master cylinder isn't so bad.

I've been pushing aftermarket ones through mine that are $75 a pop. I seem to go through 1 every year. I run a heavy heavy clutch; silly single plates.

Back to genuine Nissan for me.

As a comparison the aftermarket slave cylinders are $40. I think that too is starting to blow out; last time I flicked the boot a little clutch fluid had built up in there.

[skylinegtts]

are there any tell tale signs of a master cylinder or slave cylinder when they need replacing?

[Beer Baron]

yeah, leaking fluid. and poor clutch operation.

as fatgts-r mentioned the pedal bracket is also not so hot and can bend and/or break. Nismo make an upgraded one for R32s with more welds etc. cheap at about $80 or so.

[Cubes]

I've had my pedal box pop its welds.

In my case the spot welds broke and then continued to tear at the metal.

I grabbed a couple of pics from the nismo pedal box and noticed they have replaced the spot welds with propper welds. I had mine rewelded for $30 and its now tough as... I hope.

[Jenius]

Well I ended up changing the gearbox oil to Castrol Syntrans, and it still didn't do the job.

but thanks for pointing out the pedal bracket. I'll have a look at that when I have the chance. I'll also have a look at the connection actuator rod from the Slave cylinder to the clutch itself.

the clutch pedal doesn't seem odd or anything. I just hear the something in the gearbox still spinning or whining for a little bit when I press the clutch really quickly when I 'm changing gears. so it could be the fact that something is causing the clutch not to actuate quickly or not far enough to clear the flywheel.