Rb20 Box Noise When Changing Up Through Gears

[cloudbreak]

Hey, I've searched the forum, can't find a relevent thread so I'd really appreciate a diagnosis here... THANKS!

I've got an RB20det and box in a Gazelle (s12) and have always changed pretty tamely, and as far as I know the box only has around 100K k's on it.

Issue:

When changing up through the gears (accelerating) a WHIRRRR noise can be heard (and vibration felt in the shifter) just before the stick goes into the next gear. If I wait for the engine revs to drop below 1.5k then the gear goes in straight away with no whirr but if i change at revs above that in ANY gear, the noise can be heard.

- This doesnt happen when down shifting, I can even downchange at 5k without double clutching and it's fine.

- it's only when upshifting.

As this is a custom install, it's going to be an absolute prick to get the box out again so if there is any chance this is a simple fix or something so major that I might as well just drive to to its death, then replace the lot later then I'd prefer that (i actually have a spare box in Melb which will go in next I suppose, but im now in syd and have no time or money for a while)

As you can tell, I know absolutely nothing about gearboxes...never really had any issue with them in any of my cars.

Cheers and thanks again!

Nick

Edited January 12, 2009 by cloudbreak