There will be some gear noise in the reduced-speed gears (1/2/Rev.) but if it's really sounding off, it sounds like the needle bearings on the cluster gear are gone. Even though the cluster gear turns all the time, if it's not transmitting power, it will run quiet. Anytime power is moving from the input shaft, through the cluster gear, and back to the output shaft through 1st. or 2nd. gear, the cluster gear bearings will be loaded. If they're damaged or a few needle bearings are missing, they will be noisy.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
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