2003 Johnson ST 55 HP WRL 2 Stroke Commercial Service Manual, PN 5005483, Page 31Get this manual
SPECIAL TOOLS AND SERVICE SPECIFICATIONS OIL REQUIREMENTS
OIL REQUIREMENTS
Engine Lubricant
EvinrudeJohnson XD25 Formula outboard oil is recommended for your outboardIt contains richer additive package than other TC-W3 oils, minimizing carbon build-up and deposits on pistons and bearing surfacesIt provides 25 greater detergency than minimum TC-W3 requirementsEvinrudeJohnson brand oils are formulated to give best engine performance while controlling piston and combustion chamber deposits, providing superior lubrication, and ensuring maximum spark plug lifeIf EvinrudeJohnson XD25 Formula outboard oil is not available, you must use an NMMA-certified TC-W3 oil such as EvinrudeJohnson Ficht Ram Injection Oil or EvinrudeJohnson Biodegradable Outboard oil
PROPELLER SELECTION
Refer to PROPELLER in GEARCASE section before installing propellerThe correct propeller, under normal load conditions, will allow the engine to run near the midpoint of the RPM operating range at full throttleRefer to TECHNICAL DATA