Will not overlook to re-seal the gearbox with RTV soon after 
you’ve located the correct mix. Even although they’re referred to as “gaskets”, they won’t seal your gearbox on their very own.
If every thing appears regular, try modifying the gear-mesh. This is completed with the mylar “gaskets” that sit between the main gearbox scenario and the input/output caps. Attempt adding or eliminating some of these spacers till your gears have about 
one/8″-1/four” of totally free perform. Specialists can get replacements ($1-2) in varying thicknesses, but we recommend the rapid and filthy method of slicing your own out of a sheet of mylar.
“Groaning”, “creaking”, or “popping” all sound type-of comparable more than-the-cellphone. The ideal thing to do is to disassemble your gearbox and consider a appear at the gears and bearings. The concern will typically present by itself in the way of damaged/missing equipment tooth, toasted gears (like that photo on our property website page), or blown bearings.
My Gearbox is Groaning/Creaking:
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