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High Rmp Gear Change

Redback

By Redback,
in Engines & Forced Induction

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Redback Proficient

Redback

Posted
Posted (edited)

Hi guys. before you say its been answerd before i looked cos ive seen it somewhere myself... lol. couldnt find it.

when i go to grap 2nd 3rd 4th with a quick gearchange in high rpm it grinds.... i aint on the gas during the gearchange and the clutch is fully activated (as in fully in). and ideas. think it may be syncros or something.. maybe even clutch.

it has a thrust bearing squeak, maybe that mite be the problem.

goes in no problem once the revs have died down.

cheers guys.

Edited by Redback
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https://www.sau.com.au/forums/topic/93715-high-rmp-gear-change/
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Risking Grand Master

Risking

Posted
Posted

It sounds like you have either the syncro problem or a clutch problem.

Does the clutch have much freeplay or does the pedal pick up right on the floor?

If the clutch opperation is normal then its going to be a syncro problem it is however odd that 3 syncros would all go at once.

Before you go pulling the box out, drain the oil and fill it with dextronIII auto trans fluid. if the shift quality is better you have worn syncros, if its the same then there is more than likely something amis inside the box providing the clutch is okay

race_snooze Grand Master

race_snooze

Posted
Posted
yep will be syncros in your gearbox. And i think you mean thrust bearing not thrush :D

yeap mine did the same till got it rebuilt, new clutch, syncros, bearings, and labour $3000 feels like a new one now and so it should

Duncan Grand Master

Duncan

Posted
Posted

redline oil is great for worn synchros and cheaper than pulling the box out to replace the thrush bearing.

you can tell if it is clutch or synchros by whether the crunch happens at idle, eg car standing still with motor running. If it still crunches when you change quickly at idle it is a clutch not disengaging problem

Redback Proficient

Redback

Posted
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sorry but lol at the "the orage carrot". lol.

on topic... ill try some new gearbox oil then if that works ill just give the thrust bearing a little crc or something just to get rid of the squeel for the mean time.

lwells Grand Master

lwells

Posted
Posted
redline oil is great for worn synchros and cheaper than pulling the box out to replace the thrush bearing.

you can tell if it is clutch or synchros by whether the crunch happens at idle, eg car standing still with motor running.  If it still crunches when you change quickly at idle it is a clutch not disengaging problem

Mmm.. nice tip duncan, ta. Having some troubles with second gear myself so it would be nice to work out if its the box or the clutch (again). Anyone got a rough price on replacing synchros/overhauling the gearbox?

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