Bearings/Axles

[mfMcFroggierPod]

Purchased trailer used several years ago. I grease bearings manually every year. I noticed these burn/rust marks every year. I sand the marks off with very fine emerycloth but the marks come back every year. I would replace all bearings and races but the axles have these marks. Any clue as to what it's from....? I was told trailer sat alot very little use.

[WJC]

Maybe from heat, all though usually bluish in color, are your brakes running hot?

[clr]

It may be from rust inside the wheel bearings. You could try cleaning the bearings in a solvent but I would try replacing a bearing set for a wheel and see if that fixs the problem.

[OldCoot]

Suspect bearing race may be turning on spindle. I have prick punched a few spindles to tighten the race so it won't spin. Should not be rust with all the grease on it. Check your inner bearing very closely for pitted rollers or race.

[mfMcFroggierPod]

Replaced all bearings a year ago. Same marks noted during my bearing inspection/repack.

[Asrabbit]

That high part of the spindle is where the seal rides. I do not think the bearing rides on that part. You can check that out by sliding the bearing on the spindle and seeing where it stops. If that is the case, those marks likely just come from the seal as it turns on the spindle.

[m35a2]

That might explain the axle, but not the rust on the bearing.

Do the hubs get hot when you pull the trailer?

[2Evil4U]

Judging by your eyeball in the first shot, it is on the bottom of the spindle and on the portion of the bearing that is lowest. It appears to be fretting. This is usually the result of a bad fit from the race to the spindle and contamination of some sort. (Most likely water in this case.) (FWIW, Orange means aerobic (with O2), and black is anaerobic, (without O2) both types will result in the same problems.) Scuffing it down with crocus cloth will only make the fit worse and will exacerbate the problem. Replacement of the parts with clean spindles and bearings with correct dimensions is the only way to eliminate it.

[mfMcFroggierPod]

That sounds expensive to replace spindles? Can new spindles be welded on vs new axles? Cost one vs other??

[mfMcFroggierPod]

Originally Posted by m35a2

That might explain the axle, but not the rust on the bearing.

Do the hubs get hot when you pull the trailer?

Temps seem normal; I am just concerned about the marks.

[VinceU]

Originally Posted by mfMcFroggierPod

Temps seem normal; I am just concerned about the marks.

On a limb here but that marking may easily be a metal transfer of two dissimilar metals in very tight shaft to bearing fit. Eventually the shaft may no longer provide a tight fit for the bearing and will need to be renewed. Suggest use a micrometer to measure the shaft and check for proper clearance.