Recently I've been hearing a humming or almost rubbing sound coming from my front right tire, almost the same sound you would hear with an aggresive tread on the tire, I've taken the tire off and taken a quick look at the hub lock and the bearing but cannot find anything that looks wrong. It's a 1994 B4000 4x4 SE. Would appreciate any help.

Recently I've been hearing a humming or almost rubbing sound coming from my front right tire, almost the same sound you would hear with an aggresive tread on the tire, I've taken the tire off and taken a quick look at the hub lock and the bearing but cannot find anything that looks wrong. It's a 1994 B4000 4x4 SE. Would appreciate any help.

My front bearings made a sound like you describe. The factory forgot to put grease on the inner front wheel bearings on my '94 B4000 SE 4x4. I apparently made it about 12k miles on the greasy film that bearings are boxed with. During this first year, my local Mazda dealer would not warrantee the damage; said I should have had them re-packed although service interval recommended at 25k. They were never in water or any kind of abuse. There was some minor damage where the races had turned on the spindle. I had a private shop replace the inner bearings and re-pack all. The outer bearings were fine, of course. The inner bearing races had turned blue already.