This weekend during a test drive of added soundproofing, the front left started getting noisy and shortly later there was a pop and a slight swerve. I safely got it to a parking lot, but the front wheel bearings were metal-on-metal at that point, and the wheel had shifted outwards so it wasn’t possible to drive any further.
With the wheel shifted out I didn’t want to risk further damage when loading on a tow truck, so Christina came to pick me up and we returned with a trunk full of tools and spare bearing from home to replace the bearing on-the-spot. This would have been a ~30min job except that the spindle nut and inner race of the outer bearing had lightly welded themselves to the spindle. I returned with a dremel (and inverter to power it) – the spindle nut was removed, but removing the bearing race was not possible. I found a big metal spacer that served the purpose of keeping the wheel retained on the spindle, though it did not work as a bearing and wasn’t driveable more than a few hundred feet.
With the spacer in place it was safely towed back. The next morning with better light and bigger tools I was able to get the bearing race off of the spindle. The bearing was even available locally and I got it all back together quickly. Special attention was paid to the bearing end-play, this was set to the correct spec with a dial indicator and the bearing thoroughly greased. This was then repeated on the other side.
The front wheel bearings were perhaps the only area that I had not yet gone through since getting the bus; so the failure isn’t necessarily surprising. Both sides had minimal grease and light rust pitting which, along with the bus’s new faster speeds, contributed to the overheating and failure.