2003 Johnson ST 55 HP WRL 2 Stroke Commercial Service Manual, PN 5005483, Page 174Get this manual
GEARCASE LUBRICANT For high motor installations, the trim tab might be above the water when the motor is trimmed outSteering effort might increaseSteering effort will be reduced if you trim the motor in and submerge the trim tabwater from normal water vapor condensation within the gearcaseOverheated lubricant will give the lubricant black color and burned odorRefer to LEAK TEST PROCEDURE
LUBRICANT
Draining
IMPORTANT: Gearcase lubricant may be under pressure andor hotIf plug is removed from recently operated outboard, take precautions to avoid injuryRemove the lubricant level plug, then the lubricant drainfill plug, and drain the lube from the gearcase into containerInspect the lube and the magnets on the plugs for metal chips
Internal gearcase inspection is recommended when lubricant is contaminated or shows signs of failure
Filling
Secure the gearcase in vertical positionRemove the lubricant level plug and the lubricant drainfill plugSlowly fill the gearcase with Ultra-HPF gearcase lube through the drainfill hole until it appears at the oil level holeFilling the gearcase too quickly can cause air pockets and the gearcase may not fill completelyClean plug seal area and install the lubricant level plug and new seal, then the lubricant drainfill plug and new sealTighten them to torque of 84 to 86 inIbs(9 to 10 Nm)