Yes you can rebuild them. It's pretty easy all you need to do is press the shaft out and then you have a snap ring holding the bearing in.Remove the snap ring and tap out the bearings.
If all fails with locked up or cross threaded bolt; I removed a spindle in a few minutes by just cutting off the mower blade with a cutting wheel on a angle grinder. Then take the four bolts out and remove from top. You have to cut them off pretty close to spindle housing.
you must use a water hose to spray your deck/mower off to fail in hundred hours.. I only use a blower never used water on mine. currently have 250+ hours and counting turn free as like new never been greased no fittings..
I know this video is a few years old, do you remember where you bought the spindles from. I need to replace mine and I don't want to pay 200 a pice from dealer
well what you could do is take yours to a machine shop ( like I did) and have them install new bearings ( and grease fittings) . i think it was like 70.00 out the door. those are common bearings. I did buy new spindles though at first because I didnt realize I could fix the originals. I cant recall where I bought those, but I did pay around 125.00 ea. yeah the dealers a rippoff. If you google those Im sure you will eventually find them.