Suzuki DF25/DF30 Four Stroke Service Manual, Page 233Get this manual
LOWER UNIT 10-9
Inspect forward, reverse and pinion gear teeth and engaging dogsReplace gears if damaged or worn
Inspect forward gear bearingReplace bearing if pitted, noisy or rough
PROPELLER SHAFT COMPONENTS
Inspect push rodpush pin, replace if worn, broken, or tip is flattened Inspect clutch dog shifterReplace if chipped, worn or damaged Inspect dog pinReplace if bent or worn Inspect propeller shaftsplinesReplace if worn, twisted or damaged