Jump to content
SAU Community

Recommended Posts

Hey

Was giving my GTR a bit of a hard time yesterday and now there seems to be a slight issue with the gearbox/clutch engaging

I put the clutch into the floor and when I attempt to change gears it crunches, much like when the clutch isn't engaged

Clutch doesn't slip, not even on high RPM or launching but its starting to crunch 4th gear now even on low RPM levels

I thought it may be the slave or master cylinder leaking pressure and not providing enough clamping pressure on the pressure plate to clutch, causing it to crunch but my dad checked both and it seems neither is leaking

Fluid looks clean with no leaks, according to service records the fluid has been recently changed

Any other thoughts or ideas on what it could be causing the problem

Thanks

Link to comment
https://www.sau.com.au/forums/topic/229469-gtr-gearbox-crunch/
Share on other sites

Okay, well I thought I had it all sorted but it has started happening again

I topped up the fluid as it was a little low, pumped the clutch with the lid off and then tried again and it was fine for a few days, now its started doing it again on the odd occasion

Sometimes its fine then on randomly it will crunch into 4th for no reason

Does anyone know what the fk is up with it??

I'm going to drain the clutch fluid and put new fluid in it next week, then bleed the clutch. Hopefully that does it but some how I don't think its that as the clutch seems to work fine, no slip or anything and grips in every other gear

Thanks

It wont. If it was the clutch it would crunch all gears. No?

Dude its 4th synchro, theyre dynamite for crunching. Redline doesnt help either. Its not as miraculous as most say...

Might as well start looking for a new box lol, thats what I did! Fixed it real good.

It's happened in the past and it's been the clutch, in a previous car I had it was doing exactly the same thing but it was the pressure plate failing due to being weak causing the clutch not to engage 100% therefor making it hard to put it into gear

Also on the forums the cheap clutches that SLIDE was selling, EXEDY clutch plate and OEM pressure plate eventually started to do the same thing

Thanks

I have a GTS4 with a fairly badly crunching 4th.

Why not just try slowing down the speed of gear change?

Double clutch/heel-and-toe gears down.

5th -> Neutral -> 4th

Blipping throttle helps too

Yeah that's what I do to avoid it crunching but I'd rather not do that forever

I found with mine that double clutching did nothing - I noticed however that clutching, bringing the gearstick back slightly and allowing the revs to drop before putting it into 4th makes it smooth again 99% of the time - does not work for downshifts though so I just go straight to third, I'll try some Redline Shockproof Lightweight until ! can get the money together to try and get another GTR/Stagea box!

  • 3 weeks later...

Hey I know this is off the topic a little. My car use to crunch first at the lights and if you where a little miss timed with the clutch on the gaer change it would crunch. I got my clutch changed because all of a sudden I had a large vibration. I had cracked my flywheel. After replacing it I never crunched again. I think I am lucky my flywheel didn't let go when it finally decided to go. The only thing holding it together was the ring gear. So now I am alway carful when my car starts to crunch.

Yeah that's what I do to avoid it crunching but I'd rather not do that forever

my 4th gear synchro's have been bad since the day i bought the car. as most are saying, its a very common problem in the GTR's. ive been "double clutching" the whole time. it helps it to the point where its virtually un-noticable. and if you get it right you can change almost as fast as you normally would. you just need to make sure that you match the revs.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I refreshed the OEM injectors with the kit and connected it up. It now ideals okay even with the IACV removed. Driving still has the same cutoff issue like the 550cc injectors so the issue is somewhere else. I bought FPG's Fuel Pump Hanger. I will be installing it next, but it is not as straightforward as I thought it was with my limited wiring knowledge and no instruction on the specific model I purchased (FPG-089). I also got the incorrect billet clamp as I could not find info on the OEM sizing.
    • Stop looking at the garage floor, and turn the radio up a bit louder if there's any strange noises...
    • No. Turbo shuffle and surge/flutter are not the same thing. Specifically, on a GTR, turbo shuffle has a definite meaning. On a GTR, the twin turbos are assumed to be the same thing and to operate the same way, exactly. In reality, they do not. Their exhaust sides are fed and exhaust a little differently, to each other. Their inlet sides are fed and exhausted a little differently, to each other. Consequently, when they are "working" they are often at slightly different points on the compressor map compared to each other. What this means, particularly when coming on boost, is that one of them will spool up and start producing extra flow compared to the other, which will put back pressure on that other compressor, which will push the operating point on that other compressor up (vertically). This will generally result in it bumping up against the surge line on the map, but even if it doesn't, it upsets the compressor and you get this surging shuffle back and forth between them That is "turbo shuffle" on a GTR. It is related to other flutter effects heard on other turbo systems, but it is a particular feature of the somewhat crappy outlet piping arrangement on RB26s. There are plenty of mods that have been attempted with varying levels of success. People have ground out and/or welded more material into the twin turbo pipe to try to prevent it. Extending the divider inside it works, removing material doesn't. There are aftermarket replacement twin turbo pipes available, and these exist pretty mush purely because of this shuffle problem.
    • You can temporarily* use lock collars to keep it in place until you can do the bushes, back the nuts off, slide them in, snug back up. *temporarily is often for ever
    • Thanks for the quick reply. To be clear, when you say turbo shuffle do you mean turbo flutter "stustustu" or referring to something else? I had thought they were the same thing. When I wrote the post my intention was to say it wasn't a flutter/compression surge sound. My understanding was that a flutter sound would be occurring when throttle is released, whereas I can keep the throttle in the same position for this noise
×
×
  • Create New...