Originally Posted by Darwin Maring
Look at the old grease to see if there are any shinny particles as that is one indication of wear. Look the bearings over really well to see if they all look good. If you notice something that looks worn or different from the rest, then you might want to put in new bearings. Grease: I like to use the Red grease and it can be purchased at auto parts stores either in a tube for a grease gun or a can for non grease can use.
:as a old car guy you can buy a tool to help you grease your bearings, or use your hand but first remove it all and clean with paint
thinners, turpentine, or what ever anyone else uses once clean do as the other fellow said check everything carefully, do not play with using the old seal, (to get the seal out easy turn it around and use long thin punch and hit the edge with a hammer it will pop out fairly easily by doing this though u might have to hit a bit on each side but it will come out this part u want to make sure you replace) if the bearing looks good then use the tool I told you about as Napa sells them to, or use your hand by placing the grease into the palm of your hand (messy job) now you take the bearing and U put it on a 45*angle and start by turning it into the grease and make sure the grease is being forced into it and when you see the grease working through then you know the system your using is working. Once all done then clean your hands with thinners to cut the grease and wash with soap and water. Now you put it all back together the way the other fellow told you and he is right don't tighten the nut just tighten firm with your hands and use the new cotter Pin.