Wd40 alone is not a lubricant, it is a cleaner and is made to remove water. You need an actual lubricant or penetrating oil for lube, I prefer tri flow myself, another thing I like is a can of stuff I bought at the local motorcycle shop, its a chain lube thats meant for bike chains, I use it on my chains but also found that it works very well for lubing the bearings, it also acts as a dirt repellant of some sort and keeps dirt out of the bearings when you use it for bearings, mine look like new everytime I pop the seals since I been using this stuff. I'll have to look tomorow and see what the name of it is, but id reccomend it to anyone for bearings, chains and everything else that needs lube. Only use the WD40 as a cleaner, WD40 stands for Water Displacement #40