hey guys just bought a triton explorer in June...it came with a small load rite(think thats what its called) trailer(17 foot). it says I have to grease the bearings on the wheels...about how often do I have to grease the? what grease should I use and also once I take the cap off are there fittings to put the grease or do you just apply it by hand..any help would be great thanks a lot guys!