i put straight lucas in the rear i also notice that the diff was straight cut gears not hypoid i agree that light throttle rattle drives you crazy i think the design is causing the noise more that any thing. the lucas maybe helped a little i am going to see if 90-140 will absorb the tooth contact noise better i will post it when i do it baffles me why honda did it that way, probably cheaper since p 500 is an entry level machine.