I recently replaced my front hubs. Neither one of them showed any sign of loosnes/wiggle or grinding when I jacked up the tire like you normally get with bad bearings. In fact mine was making the bad bearing noise when I bought it, road testing showed in increase in noise turning both directions, but jacking up showrd both tires turned smooth and didn't wiggle at all.... So I just lived with the noise. After about a year and a half owning it, I finaly noticed some abnormal tire wear on the driver front, so I changed that bearing. Let me prepare you, this will be the worst bearing change you will ever do. Normaly its a half hour job if you take your time. I will spare all the details (you can search my posts if you are really curious) but total time was about 4 hours spread over 3 days with the end result being removing the knuckle and using a hydraulic press to remove the hub from the knuckle...... Being recently changed yours will hopefully not be that bad....
Anyway, with both old and new bearings in hand, I could not tell any difference when spinning them by hand, the old one seemed fine, but when I installed the new one and put everything back together, the noise was gone, so obviously that was the problem. The other one went bad a few months later, and despite the knowledge I gained on the first one, it was an even bigger PITA to change... But, all bearing noise is gone... I had forgotten what BFG's sounded like on the highway, lol....
As for the bearing being changed recently, that in no way means it cant be bad again. Amazon and ebay are overflowing with cheap crappy bearings. You can get them for less than 1/2 or even 1/4 what you would pay for a quality bearing, but they tend to last 5-15k miles vs 50-100k+ for good bearings.... Dony buy anything other than moog, timkin, or skf. I bought a grand cherokee last march, and a bearing went bad in september. It was not hard to diagnose, my wife said it felt like the jeep "slipped" on the last turn on the way home then got really noisy.... All wheels on the ground I could push on it and see the wheel wobble. A lot.... Parked it till the bearing came in and upon disassembly, it turned out the brake caliper was the only thing holding the wheel on the jeep. The bearing had no rust on it (recently changed) and also had not brand name, meaning it was a cheap amazon/ebay bearing. If she had been further from home when it happened, I don't believe the jeep would have made it home.... Saving $100 on a bearing isn't worth that, imo.... Up side, the job only took 20 min....
