Spindle wear-at what point to replace

[Skniper]

Doing my second knuckle rebuild on my 62, last one was several years ago, but they are shot again. It currently has about 250K on the odometer. Did not replace the hub/wheel bearings last time so I am assuming these are originals.
Replacing ALL bearings/races/seals/gaskets this time with good OEM/Japanese bits and HD Marlin inner axle seals.

So, the wheel bearings had been noticeably loose or worn for some time. Now that I have both sides of the front axle torn down I noticed some wear on the spindles where the bearings ride. The wear is mostly on the outer bearing side and can be easily felt on the bottom, weight bearing side of the spindle shaft. The wear is enough to feel and catch a fingernail on.

I'm thinking this is not a good thing and the spindles should be replaced. Looking for opinions to confirm this or tell me otherwise.


FWIW, I have a set of new oem replacement brass spindle bushings in the box.
People have talked about having to hone these down to fit the birf shaft. The new bushings I have slide right over the birf shaft with no problem, do some fit well and some dont?

So should I get new spindles?....gives me a good excuse to use these bushings I bought forever ago.

thanks.

 

[KLF]

In theory, the spindles shouldn't see any "wear" because the bearings are supported by the spindle but it isn't part of the wearing surfaces. They've lasted this long, I probably wouldn't replace them.

The brass bushings will compress slightly when you press them into the spindles. Make sure you check that the Birfield can freely spin in the bushing AFTER you've installed them into the spindle. Yes, I've had them be too tight and had to hone them with a brake hone.

 

[ntsqd]

The reason for the wear is that the bearing's inner race has spun on the spindle. That is a direct indicator that the bearing pre-load was too low at some point in the past.

 

[Skniper]

Yep thats sounds about right. The big retaining nuts on the hub were very loose when I took it apart and the big thrust washers now have a groove "machined" into them.
I was very meticulous about setting the preload/torque to spec. All I can think is that the bearings finally wore enough and things began to loosen up. Or maybe checking hub bearing preload should be a semi-regular maintenance item.
I still may replace the spindles anyway as they do have a noticeable wear groove in them....and just flip the washers over and use the other side.