Seal failure on a Dexter EZ Lube spindle bearing hub, which took out the brake shoes and necessitated a massive rebuild project on all 4 hubs.
This failure was caused by improper use of the EZ Lube zerk fittings. The axle needs to be jacked up and the wheel rotated while grease is pumped in slowly with a MANUAL grease gun, not an air or electric powered gun.
I highly recommend Lucas Red '"N" Tacky grease, as it's what I've used ever since my days on the dairy farm, and have never seen a bearing failure due to this grease.
Red "N" Tacky grease:
https://amzn.to/2T8YfG0
Lincoln manual grease gun:
https://amzn.to/3pzVdqj
LockNLube zerk coupler, the best grease gun accessory ever created:
https://amzn.to/3iFsZJF