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Hi all, just a bit of a question regarding gearbox/diff noises...

Is it normal to have a slight whine/whirr coming from some part of the drivetrain in all gears when you back off the throttle??

This noise is coming from a 91 NA 1.6 (long crank), and is most noticeable in 3rd.

The noise sounds just like the noise typically made when you change down a gear (eg 3rd to 2nd) and ease the clutch to increase the engine speed to match the gearbox (instead of blipping the throttle).

There is no unusual noise when driving at constant speed or when accellerating, so I assume it is not a thrust bearing, as it would appear under accelleration as well (I think). Correct me if I am wrong. Also, it is not loud, but just audible if you have the radio off, and are listening for noises.

diff.

Try changing the diff and gearbox oil.
Mine makes a noise similar to that which i knew when I bought it and the NRMA inspection suggested doing the above, which helped.

yep.....same issue here. I went & bought a spare gearbox......then the diff blew.
However there have been forumites with the similar or same issues but it turned out to be the gearbox.

thanks for the replies everyone.

I suppose the best course of action is to change the fluids in diff and gearbox asap, and wait for something to fail.

Sounds like there isn't much point pulling things apart till the problem becomes more apparent.

I've got a similar noise when backing off in 5th (in the 6 speed, used to be 4th in the 5 speed) and it doesnt sound too nice i can tell you that! But it only happened when i put my ceramic button clutch in it, the organic didnt make a noise. I'm putting it down to less cusioning making more noise. Diff is brand new center and a fully re-built case so its not the diff.

Dave