[chadr03]

Is there any backlash in the gears? (Can you hold one shaft and slightly twist the other one back and fourth?). Gears can make a lot of noise if they are meshed too tightly. Did y'all make the gear housing or purchase (Center distance might be too small)? If the pressure angle of the mating gears is off you can get a really noisy gearset. You might try to mix and match similar gears to see if some might have been manufactured thinner and thicker. If all else fails they might quiet down by wearing them in a bit.

I'm not real familiar with the andymark custom gear boxes, but design gears daily.