Why black marks on wheel bearings?

[K85 Octane]

Pulled these off to inspect. They have about 900 miles on them. One side was a tad loose and the other seemed good. What does the chatter black marks mean? Should I put them back on or is there something afoul? Also, the spindles look fine.These are off my '68, a truck that has NOT seen water or mud crossings lol

 

[toomany]

Do they feel fine? Gritty? Loose? Tight? Does the black come off? Looks like the metal is discolored...not "baked on". Name brand or off shore bearing? Do they fit the spindle well? Come off easy?

If they feel fine, don't make noise and are still tight, could be cheap metal that just discolored. Seen that happen before. What type of grease did you have them in?

 

[K85 Octane]

They feel all around fine. They seem to fit well on the spindle too. I'm just trying to hunt down two issues.

1) Squeaky brakes (think transit bus only worse)
2) Groaning from front end during hard turns, both ways.

Rear problem
3) Poor pad alignment on rear disc

 

[K85 Octane]

Oh yeah, black does not come off. Bearings are no name brand. They just came with the hub kit.
I'm using the red high temp disc brake wheel bearing stuff, made in USA.

 

[campfire]

They feel all around fine. They seem to fit well on the spindle too. I'm just trying to hunt down two issues.

1) Squeaky brakes (think transit bus only worse)
2) Groaning from front end during hard turns, both ways.

Rear problem
3) Poor pad alignment on rear disc

Groaning...like you'd get with loose or shot front wheel bearings?

 

[sweetk30]

in my opinion if they cant even put a name and part # on a bearing it should not even be sold.

last time I was at autozone there not selling timkin anymore and its store brand only . pulled it from the box and nothing on it . back in box and I went home and hit up www.rockauto.com and got my timkin in 2 days .

 

[K85 Octane]

I'll try searching the numbers on it. Damn things don't have a country of origin or brand stamped in them lol. At this point, I can request new bearings from CPP but I'd rather not have any troubles later on. Here's hoping they are simple 71-72 front disc replacement bearings.

 

[chulisohombre]

Look kind of like heat tinting like the hearings are overheating. Possible that the were loose and spinning on the spindle instead of against the hub? That would cause more gear and sounds going around corners as being loose will Let the hub angle up and put more side pressure on the bearings.