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well my 4th gear clunks/ crunches, especially when coming down from fifth...

you cant shift down quickly and if you dont bring it down from fifth and for a split second leave it in neutral before shifting down to 4th then it crunches... and if your get up it a bit and change real quick from 3rd - 4th it sometimes crunches then too....

ive been told it is a lazy sinchro? so i had a lighter oil/ less thick put in to make it easier on it, but it still does it.. what is it? and what should i do to fix it?

also it might sound weird but when i put it in to 4th if as im doing that i kinda move it towards 2nd it usually wont do it...

1 3 5

| / |

2 4 R

if that makes any sense...

Edited by 02_FNE
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yeh its your syncro, done alot of highway racing have we?? or have you driven around at like 40km in 4th gear?? unless you want to pull the box apart and get it refreshed your going to be stuck with it...

and going over to second before you put it into 4th has got to do with using different forks in the box...i cant really explain that one to well.

have you tried double clutching? rev match.

well the syncro itself will cost you...35$ max from nissan or wherever. but the process to put it in is not as cheap... gearbox has to come out and pulled apart...

if you havnt raced or done any damage to the box then the previous owner probably did.

does it go in easier when you double clutch it? and rev match.

If your box is getting really noisy/crunching/grinding alot then you should look at trying some redline shockproof oil. Good for old worn boxes. Otherwise just use some Castrol VMX80 and some nulon additive, made my box feel almost new again.

Also as stated above always double clutch, it is much easier on your box.

ok cool, thanks for the help guys, ive also been told that i should replace the white nylon sleeve thing that the shifter stick sits into as it wears out and gets sloppy, so ill do that and also double clutch aswell as a treatment..

i know a few good peeps in the mechanics seen that might be able to help me out with getting the synchro changed..

it sh*ts me aye, i just want it right..

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