Noisy Gearbox in gears 1 2 &3, 5 speed

Engines, Transmissions & Final Drive questions and answers

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Bevan
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Postby Bevan » Wed Jul 25, 2007 12:59 am

I would say it's your diff. Will sound like it's coming from the gearbox, but it's actually the diff whining in most cases.

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bigdog
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Postby bigdog » Wed Jul 25, 2007 11:27 am

It will be either the clutch throwout bearing or the spigot bush in the flywheel. As you need to remove the box to replace either, do both at the same time. Hope the gearbox bearings needed doing - thats an expensive way to fix the wrong problem... :frown:
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manga_blue
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Postby manga_blue » Wed Jul 25, 2007 2:09 pm

I'd say front of gearbox. See if these fit:-

- front of gearbox noise will come at anytime the front of gearbox is turning, i.e. when driving AND when in neutral with foot off clutch

- a clutch throwout bearing will make noise when it's loaded by the clutch being pushed in - your car stops making it when you push the clutch in

- flywheel spigot only makes noise when the gearbox input shaft is turning at different speed from engine - your car makes the noise when driving in gear, i.e. when flywheel and input shaft speeds are locked together by clutch

- diff only makes noise when car is driving - your noise happens even when car stopped

- back of gearbox, as for diff

My guess is incorrect, faulty or wrongly installed gearbox main front bearing.
’95 NA8

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Benny
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Postby Benny » Wed Jul 25, 2007 5:51 pm

Have you checked the rubber boots which the shifter goes through?
There are 2 of them, and if they are cracked or broken, they can let a lot of noise come through from the drivetrain.
This is the cheapest and easiest thing, so I would be checking that first.
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JBT
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Postby JBT » Wed Jul 25, 2007 9:09 pm

Were the selector shaft bushes replaced too?
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flycasta
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Postby flycasta » Wed Jul 25, 2007 11:52 pm

Sounds to me like the front gearbox bearing or, it is weird that the noise is only there when in 1st 2nd and 3rd which means it is not there when the mainshaft is locked or engaged in overdrive, which could indicate the front mainshaft pilot needle roller bearing, located inside the rear of the input gear, is either stuffed or the area of shaft or the inside of the of the gear it runs on is. Once the mainshaft is locked it no longer turns.

By the sounds of it you didn't change the clutch when you did the gearbox, the clutch bearing could have been bad or when it was refitted may now be reset to far and is rubbing/semi engaging with the clutch creating the noise because it is not fully loaded and not completely clear of the clutch.

I would get another opinion from another gearbox repairer before buying another box.


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