If My suspicions are correct and that is a trash drain for the belt side of the case : Assuming it's a small oil leak , and your transmission calls for 80/120 gear oil : Don't use synthetic oil as it tends to find leaks . Try straight 90 weight with some STP , Motor Honey , etc ( Thick Snot ) or one of the Lucas type leak preventative additives . You could top off the transmission for now with any cheap motor oil to establish how low the oil level was and get an idea of how bad the leak is . Than drain and refill with the expensive proper oil .
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2011 BMS KING COBRA 150 Sold
YERF DOG SPIDERBOX's Sold
YERF DOG 3203's. Sold
MANCO SILVER FOX. Sold
2009 POLARIS 500 HO SPORTSMAN 4X4
2002 POLARIS 500 HO SPORTSMAN 4X4
2000 POLARIS MAGNUM 2X4
HALF A DOZEN CHEVY 4X4's
NEED-MO-BUGGY