2003 Polaris ATV Trail Boss 330 Factory Service Manual, Page 158Get this manual
TRANSMISSION 18Inspect gear bushingReplace if half of teflon surface is gone
NO Measure pitches
TRANSMISSION ASSEMBLY
19Inspect output shaft gear, sprocket and bearingReplace if necessary1Assemble input shaft assemblyNOTE: Install bearings with numbers and letters facing out so they can be read after assemblySprocket cogs face the dog gearOutput Shaft Bearing NOTE: Input gear cogs face inward on input shaftSprocket Dog Gear Input Shaft Sprocket Gear Thrust Washer