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well Ive just had my manual conversion done and everything seems fine except for the gearbox making a whining/rubbing noise.

It makes the noise through 1st 2nd and 3rd gear but is ok in 4th and 5th. If the car is at idle it makes the noise but goes away when I push my clutch in.

I'm new to manual gearboxes so I Dont know much at all, so any help or info would be appreciated.

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Gearbox bearings for sure. Not a thrust bearing, as the sound goes away when the clutch pedal is pressed...disconnecting movement from the gearbox and leaving it the logical source of the problem.

Unless you've bought a gearbox with some straight cut gears, you've acquired a dud gearbox. Will need a recondition and probably cost you $1000 for the privelege. Sorry to be the bearer of bad news.

i have the exact same problem mine being main shaft and input shaft bearing are shot, i have play between the shafts, and will grind 5th 2nd and 4th. this happened to my car when i bought it thanks the previous owner not having enough oil inside. i replaced the gearbox oil with a fully synthetic oil and my box has lasted a over a year and is still going, the 33 box is a very strong unit in that year i covered 30k worth of highway, city driving, through the mountains, and plain straight out abuse by abuse i mean shifting from first to second to third as hard and and as quick as i could, and about a dozen burnouts to destroy worn tires after a full days worth of abuse.

if i was you keep the box till it blows by then have some cash saved up and build it tough so then you can forget about it, in the end its up to your but if you pull the box apart not to replace the bearings, you might as well replace the 10+ year old syncros (how ever you spell it) and then one or two of the gears might been worth so replace them two. get the idea if your going to pull anything apart to fix do it properly and it will save you in the long run, bty way im talking from experience and i hope this long post gives you an idea as to what to do.

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