My front wheel bearings used sodium grease. I opened up the hubs, pulled the bearings and washed everything.The bearings are fine, but were fairly dirty. The existing sodium grease was still workable, but was dirty. I'm glad i cleaned it. I cleaned everything and switched over to a modern lithium grease and repacked the bearings.

My back bearings i don't want to open up and worry about shimming and doing a whole bunch of cleaning. My goal is just to get operable for a season or two, and then go deeper. The more i open stuff up, the more i need to go further than my time allows. My question is...since the rear wheels have a lubrication fitting and the grease is lean...do i pump in lithium or continue with sodium or just bite the bullet and pull the bearings now?