Spindle damage?

Really hard to tell from the photo. Can you feel the mark with your fingernail? Do we know what caused the groove?

I have cleaned up worse with Emery and let em roll with new bearings. Test fit the new bearings to the stub for slip fit all the way on with no slop and let it roll, I say.

 

I feel the same way. If there's no slack I'd keep on rocking it
I highly suggest to use Stemco Voyager series wheel seal.

 

Just keep your eye on oil leaks, if none detected, you'll be fine. Also, it'd be wise to double check on spindle nut for tightness after 1000-2000 miles of running, after everything settles. If it needs minor or no adjustment you'll be totally fine in my opinion. Good luck and be safe out there.

 

Mic it vertically and horizontal to get an idea of how much wear. Most axles I encounter with higher mileage usually have slight fretting on bottom side. Whatever you decide, go back with reputable bearing like Timken, Bower, or NTN.

 

I have changed a number of seals and wheel bearings over the years. It is a little trick to putting them back together.

YouTube Truck wheel bearings replacement.

I keep a laser temperature gun in the truck to measure hub temperatures. If you have a hub getting hot you have a problem. My temperatures loaded run between 88-150 f.

I back off the wheel nut only a quarter of a turn after tightening up. 12 o-clock to 9 o-clock.

It's a balance of not too tight, and not too loose. And too loose will cause a seal leak

 

Looks like it's HN spindle of Hendrickson trailer axle. What you had inside? oil or grease?