After cleaning/re-packing the wheel bearings on my TT the last couple times, it looks like the bearings are spinning on the spindles. There is a circular groove developing in two places. The thick washer under the castle nut (tang washer?) has a groove where it contacts the outer bearing and also the shoulder (on the spindle) that contacts the large inner bearing has a similar groove in it. The red grease I'm using also turns black at these two points, but stays red everywhere else. It has only been 1600 miles since the last time everything was apart and already the grease is black.

They are Dexter axles, 6 lug drums and the trailer weighs 9,000 lbs fully loaded.

What could cause this to happen? Am I setting the castle nuts too tight? Too loose? I inspect the bearings and races every time and all looks smooth and pretty. Could I just be misinterpreting the signs and this normal?

 

Yup nuts have been tightened too tight. Damage is done I'm afraid, you could buy new bearings and hope that they will fit tight and also the axle spindle strength is not compromised or just get a new axle. I always use the best synthetic grease I can find.

 

Take a sharp center punch and lightly punch dimples all around the worn area. It will probably take a few hundred light dimples for each bearing. Do not hit too hard or else you will never get the bearing back on. Rather too light and need to redo the dimples than too deep. Too few dimples will mean that it cannot carry the load and the bearing will come loose again.

The alternative to this is to find a knurling tool and knurl the area, but the chances of finding a tool to do this in situ is remote, so the dimpling is the next best thing.

Let us know how this worked for you.

 

Thanks very much for the ideas - I like to be creative when possible instead of just spending money and replacing parts.

Just to summarize, the spindle/bearing joint has been worn and diameters are now wrong due to the spinning? What is the ideal difference between the spindle OD and bearing ID? Just a couple thousandths of an inch? Before I start any modification, I'd like to take some measurements and know how far I'd have to go to get back to correct.

 

Mexstan gave you the suggestion I was going to offer. The ideal clearance is zero or even a negative that requires a press fit or warm the inner race and chill the spindle to get it on.

 

Locktite 648 or similar, you will need to heat the axle somewhat fierce to remove the bearing afterwards.

 

I wonder if they make micro sleeves for trailer spindles.