1999 prerunner(2wdr) front bearing lubrication

I'm replacing the lower ball-joint assembly, both right and left. I had a ball joint fail, basically the wheel came off, flopping around. Fortunately I was in a parking lot going about 3mph. I'd like to repack the front wheel bearings while I'm doing this but I can't find much info, some info says ..take the cap off but no pics. Some say, these are meant to be permanently sealed. Can I repack these with grease without taking them apart? It looks like that metal plug that might come out so I could get to it. If so, how do you get that off? I bought this new in 1999, only had it in the shop once, I fix what I can myself, been a good truck, trying to keep it going.

 

PreRunner, right? Nope. Those bearings are not serviceable. You'll know if the bearing needs to be replaced.

https://youtu.be/gap4lpb_ROY?t=26

 

OK, was afraid of that. The bearings have 259K on them, still seem OK but I'd like to get some lube in there somehow. I just saw a vid where they took off the inside dust cover, I may take the dust cover off and put just a little thick oil in there that might make it's way around at least a little bit. Maybe a waste of time but whatever. Thanks for the info!

 

Since my bearings are original with over 250K, I drilled a small hole in the inside dust cover and shot a cc of synthetic gear lube in each one, tapped the hole and put a screw in there. Hoping it might re-saturate some grease in there. That old Amsoil gear oil is some very creepy stuff, not much doubt it will reach the rollers to a degree. Thought it wouldn't hurt as long as it doesn't get on my rotors. Still waiting on my ball joint assembles, driving my 2wd 86 Toyota with no AC in central tx in the mean time.

btw, after I put the cc of gear oil in each hub, both front wheels spin several times longer than they used to when off the ground. It was obviously gummy/dry in there, not surprised of course.