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hey guys

lately ive been experiencing problems with my gearbox. at a specific rev the box will crunch

between 1st to 2nd and 2nd to third.

but also if im down gearing i can hear a winding sound when in second gear, even if that clutch is

in!

ive been searching on this forum about box rebuilds and want ti get all the bearings replaced along

with the pilot bearing and throw out bearing but since i dont know much i dont want to go to the guys

and say rebuild this the will rip me off and probly change synchos and stuff that dont need changing

all the gears go in and out with out a problem just dont know but the high rev crunching.

can someone please help and tell me what i do need to replaced so i dont get ripped of :)

and im also going to to the diff and gearbox guy in seven hills apprently he's the best with rb boxes

cheers every one !!!!

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As jack said mate if your crunching gears at hi rpm your syncros are most likely glazed and 90% worn out.

How many kms are on the box? how much power do you have? how hard is it driven? what oil have you been using and how often has it been changed? The answers to these questions will tell you if it is time for a birthday or not.

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its done 120 xxx ks not sure what oil its just been imported 2 years ago

ive gotten quotes for 1100 for 2nd 3rd synchos and bearings

so its the sync that makes it crunch

ill try the oil 50/50

ive been told to use the nulon additive as well

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the box sounds f**ked so no matter wat you do to it atm its still gona be f**ked, 120,000kms on a import manual isnt that bad if i were you i'd get the thing rebuilt properly the first time.

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i'd chuck some redline oil in it.

else you gonna be up for like 2k to get a rebuild.....

its done 120 xxx ks not sure what oil its just been imported 2 years ago

ive gotten quotes for 1100 for 2nd 3rd synchos and bearings

so its the sync that makes it crunch

ill try the oil 50/50

ive been told to use the nulon additive as well

Why you would even consider rebuilding an RB20 box is beyond me when you can pick them up for $200+

$1100 for synchros & bearings or you could buy a 25 box for around that and if you plan on further power mods you wont have to upgrade later or worry as much about breaking another box :P

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Why you would even consider rebuilding an RB20 box is beyond me when you can pick them up for $200+

$1100 for synchros & bearings or you could buy a 25 box for around that and if you plan on further power mods you wont have to upgrade later or worry as much about breaking another box :P

R33 GTST's have RB25DET boxes in them from the factory Ben :)

Try some light weight redline shock proof oil and ease up on the old girl and it might see you out. Other wise get it rebuilt not just repaired, next thing you know you will be crunching 5th ad it will blow. Do it right and do it once.

Good luck.

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yer i know the gearbox cost around that much but your taking a chance with that too.

id rather pay more and know its not going to fair for a long time

lol andthe guy who was talking bout rb20 boxes

cheers for the info guys ill keep you posted :D

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