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most of the time when i quick shift from 1st to 2nd gear i can feel the gears crunching together, but you dont hear much of a crunching.but if i gear down e.g- from 4th to 2nd it never crunches.

if im driving normally from 1st to 2nd it doesn't crunch at all.

recently did a gear box oil change using standard oil, and was doing it before oil change.

would it be my 2nd gear syncros.

i heard mayb using redline oil may help..

anyone got any suggestions....cheers

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Hi mate...

I've got similar problems...

I've got an R33 RB25DEt and I love it.. My transmission is fine at slow changes and quick shifting but as soon as I get over about 120km/h... whenever I change gears... the teeth grind...

I've been told the syncros are half stuffed.. I don't really know much about transmissions so if anyone else can shed some light on the subject, that'd be great.. I could reccommend changing your oil as well... get some good oil this time..

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Redline or use some slick50 treatment. Or Nulon. I think Slick is the best. Couldhelp reduce the problem. Since you have already replaced the oil I would buy a ttreatment of some sort...siphon out a little gearbox oil and add the treatment. Drive for 1000kms see if it gets better...If not - take out a little bit more and add another additive...

Not sure if it will be bad to mix but the box doesnt sound thmuch good anyway...

Redline is more just a decent gear oil - I think the traeatments have more of a chance of working.

Edited by benl1981
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I just changed the oils in my r33 gtr to redline synthetics and the gearbox is alot smoother however I am now getting a clunking noise in reverse that is amplified by this oil. I have been told the noise is normal though but it is anoying.

Would recomend it though as it was stiff through the gears before and had a it of a whirring sound coming from the drivetrain that has significantly been reduced.

sb..

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i changed my gear box oil to reline synthetic. so far ive driven 150 k's after changing the oil. changing into 2nd doesn't grind and crunch anymore, and the gear shifting has gone smoother. I did not adjust my slave cylinder as the mechanic said i only needed to adjust it if it was crunchin in every gear. So far so good.

Thanks for the help!

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I had synchro issues with 2nd & 4th gears..

Changed to Redline Lightweight Shockproof, synchro issues resolved.

I would rather try a $130 high grade oil first than get my box pulled down and the synchro's replaced.

Hmmm let me see which is it $130 or $1500 for parts and labour getting the box pulled apart..

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