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Rb25 Gearbox Still Grinding.

Shadex
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Shadex Collaborator

Shadex

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Hey all, You might of read that ive been having some problems with my gearbox. Anyway ive tried alot of things. Ive put Redline Shockproof Lightweight oil in there, After about 500kms it hasn't fixed it, Ive tried changing slower, Changing faster.. Giving it a little rev inbetween gears.. And i honestly don't no whats left other then them ripping my box out to see if its my clutch.. Cause lately it doesn't wanna get 1st in the mornings i have to let the clutch in out in out and keep trying to get it in, Its the same with reverse, Before it just had a slight grind going in to 3rd.. Probably once in 8 times.. Now it will do it once in about 5 or 6.. and now its started doing it going in to second from first.. So its definitely getting worse, Has anyone else had this problem or know anything that it could be?

It shouldn't be the clutch because its high up the peddle.. The clutch is a new HD 6 PUK Ceramic clutch. I cant just take it back to the place either cause a mate of mine did it

and i haven't been out to get in to contact with him since -_-

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mid life crisis Veteran

mid life crisis

Posted
Posted
Hey all, You might of read that ive been having some problems with my gearbox. Anyway ive tried alot of things. Ive put Redline Shockproof Lightweight oil in there, After about 500kms it hasn't fixed it, Ive tried changing slower, Changing faster.. Giving it a little rev inbetween gears.. And i honestly don't no whats left other then them ripping my box out to see if its my clutch.. Cause lately it doesn't wanna get 1st in the mornings i have to let the clutch in out in out and keep trying to get it in, Its the same with reverse, Before it just had a slight grind going in to 3rd.. Probably once in 8 times.. Now it will do it once in about 5 or 6.. and now its started doing it going in to second from first.. So its definitely getting worse, Has anyone else had this problem or know anything that it could be?

It shouldn't be the clutch because its high up the peddle.. The clutch is a new HD 6 PUK Ceramic clutch. I cant just take it back to the place either cause a mate of mine did it

and i haven't been out to get in to contact with him since -_-

have you given thought to the fact ya g/box might be on its way out grinding inbetween gearchanges suggest to me the synchro;s are heading south for the winter redline oil is just a patch up at the best of times if its worn its worn oil wont fix that sounds like rebuild time to me

R338OY Veteran

R338OY

Posted
Posted
whats left other then them ripping my box out

:down:

Yeah i've got rough synchros too. I doubt fresh oil will fix it. If you've tried everything you might have to live with it until you can get a 'box rebuild. Fresh synchros, dude it will basically be a brand new box and change very smooth.

Have you considered the clutch fork is screwed? The slave cylinder is also known to be a common weak link the in RB25 box, there's plenty of threads discussing it. That *may* make changing gears harder.

GL with it mate.

Shadex Collaborator

Shadex

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Im still kinda a newb with cars =( Im not sure were the master or slave cylinders are, I have checked the clutch fluid and its on the level sign ( the full sign ).. But if it would make any difference.. When i let the clutch out.. i hear this kinda clunk.. like the clutch is engaging but really loudly.. and thats just letting it out, it doesn't even have to be in gear.. a mate of mine said its a something bearing in the gearbox i forgot what he called it lol.

Im not sure if thats what your talking about R33boy.

Shadex Collaborator

Shadex

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Posted (edited)

Ok! The Master and slave cylinders are fine.. When i went to Exhaust Tec today, Mark checked over them for me cause i told him the problem i had while he was fixing my exhaust. And i asked him if he new what the problem could be, and he pretty much said drive it till it brakes and don't worry to much about it till then, cause there a strong box.. Lol. So i don't no where to go from now :blink::P

Edited by Shadex
Cubes Grand Master

Cubes

Posted
Posted

Buy an $8 bottle of brake fluid and do it your self with from memory a size 10 or 8 small ringy.

First off I usually suck the fluid out of the reservoir then refill and then drip bleed. So crack the master cyls nipple (if it has one) and drip bleed until the fluid is clear; then do the same for the center box thing if your skyline has it and then finally the slave cyl. Once fluid is nice and clear get some one in the car pumping the pedal; hold the pedal to the floor then crack the bleed nipple on the slave cyl until just before fluid stops exiting the nipple; then have th person pump the pedal again and repeat.. Make sure you keep the master cyl full of fluid. :bunny:

Shadex Collaborator

Shadex

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Ok, Update.. Im going to get the lines done when i take it to boostworx next week cause they have to do some work on my car anyhow. But.. I have noticed lately.. Its been getting harder to get in to gears.. and if i take off fast in first for example, i clutch to go to second it feels like im yanking it out of gear with no clutch.. its a really rough feel like a jerk as it comes out.

So im wondering if i borght a dodgey clutch :S

sly32 Proficient

sly32

Posted
Posted

my gearbox was feeling a bit wierd it use to crunch from 1st to 2nd at high revs, then that stopped and it started happening between 2nd to 3rd at high revs, now today i was just driving normally changed from 2nd to 3rd and bang, so defently pull your box out and get it rebuilt, its a bitch when it gores driving normally,

JV

charlie25T Proficient

charlie25T

Posted
Posted

The same thing On my box................... Redline shock proof is no fix neither is Royal purple

I changing oil to Castrol VMX80 and see if going back to basics will help

some times normal oils is suited better

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