A good thing about packing your bearings is the bearing can be inspected to be sure it's not worn or needs replaced.
In 2019 we pulled a camping trailer on our trip to Alaska. 12,103 miles total. I inspected and packed my own bearings. Not a big job really. I've done it for years. All the bearing appeared fine.
Then a Saturday afternoon just north of Wasilla heading south a bearing came apart. Before I could get stopped it took off the castle nut, outer bearing came apart in pieces and the hub rubbing on the axle totaled the axle. When I jacked up the camper the wheel fell off. There was nothing any longer holding the wheel and tire in place. We were lucky we didn't lose it going down the road. That would have damaged the trailer and put other travelers at risk of a lose tire in the road.
Fortunately we were about 1/4 mile from a repair shop altho he did not have an axle. It was just a 6000 lbs axle, nothing special, but no one near Wasilla had one. We had a 2 axle trailer and were able to slowly limp it to the guy's shop on the 1 axle. Since it was Saturday afternoon we had to wait until Monday, drive to Anchorage, and luckily we found a place that carried axles. We were back on the road by Monday evening. It was not a cheap repair.
There's a lot of miles in Alaska and Canada where if we had that problem in other locations it could have been very bad time and a lot more expensive getting repairs.
Even a bearing that looks good can go bad. For that long of a trip and the remote places you'll be traveling if you don't want to do the inspection and repack yourself paying a few dollars before you leave can be a lot cheaper than losing a bearing in Alaska.
