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well i have diagnose that my clutch is not disengaging so im replacing the clutch plate, pressure plate and throw out bearing. but to be sure does reverse gear have a syncro because my reverse grinds bad trying to get it and my other gears are not the smoothest but no grinding problems, so before i spend my money on these parts a want to be sure its not a synchromesh that is buggered. Also I have adjusted my clutch and made sure all hydraulics are working.

Nissan R34 gt (non Turbo)

70000km!!!!

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reverse does not have a synchro. I have never seen a synchro on a reverse gear. The reason reverse crunches is because it is a straight cut gear, which is also why it whines driving in reverse

reverse does not have a synchro. I have never seen a synchro on a reverse gear. The reason reverse crunches is because it is a straight cut gear, which is also why it whines driving in reverse

RX7's have a synchro in reverse gear.

But to the OP, the clutch won't be your problem. Clamp the line to the slave cylinder and check pressure at the pedal. If the pedal falls away then you could have a master cylinder problem. The adjustment you have made could also be wrong. Remember that too much adjustment can also cause the gears to not engage and will also cause it to crunch in reverse/1st

Cracked pedal box will cause it

Broken pivot ball or throwout fork will cause it

Detached throwout fork retaining spring will cause it

Heavily damaged spigot can cause it

70k on an R34 and you can bet it won't be the clutch plate or cover. Still could be but it's the least likely of all the things. It would have to have a broken spring in the diaphragm or plate for it to not disengage properly

reverse does not have a synchro. I have never seen a synchro on a reverse gear. The reason reverse crunches is because it is a straight cut gear, which is also why it whines driving in reverse

actually it crunches because there's no synchro. you can have a synchro on straight cut gears no problem.

reverse is straight cut because it's easier and cheaper to manufacture (also slightly stronger which means it can be sized smaller and leave more room for the forward gears) which is a sensible choice given you spend 99% of time in the forward gears.

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