I think there are three types of bearing setups on most trailers. Never-lube, easy lube and standard type. You can look at your axle info you got in that huge pile of books and papers you got when you purchased and find out which of these you have. Then go to the axle manufacturers website and see what they have to say about how to maintain your setup.
No man has a good enough memory to be a successful liar. Abraham Lincoln
2016 36FBTS Pinnacle
2016 F350, 6.7, 4x4, DRW, long bed
B & W Companion 5th wheel Hitch