2008 Polaris ATV Sportsman 300 400 H.O. Service Manual, Page 28Get this manual
MAINTENANCE NOTE: Maximum torque for the screen fitting (C) is 25 ftlbs(34 Nm), do not overtighten19Install new oil filter and turn by hand until filter gasket contacts the sealing surface, then turn and additional 12 turn20Remove dipstick and fill oil tank with qts(1.9 L) of the recommended engine oilReference Mark on Tank C
Recommended Engine Oil: PS-4 PLUS 2W-50 Synthetic 4-Cycle Engine Oil (PN 2876244) (Quart) Ambient Temperature Range -40 to 120 F
15Install oil hose on fitting (C) and install clamp (D)
21Prime oil pump using the "Oil Pump Priming Procedure"Stop the engine and inspect for leaks22Re-check the oil level on the dipstick and add oil as necessary to bring the level to the upper mark on the dipstick23Dispose of used oil and filter properly