Can or should these threads on a pinion be repaired?

4 ugga dugga and send it.

Your probably right. But I'd try a chase or thread file. Red jizz and a new nut. Maybe!

 

I would get on vanderhaggs site and find one that someone else turned in for a core that has bad side gears or something simple like that and then rebuild that one…probably just put new side gears in to be honest. I have changed out 2 trucks from 4.89 to 3.90 and 4.10 for pennies on the dollar of what it would have cost for rebuild units (actual parts cost including the cores probably around 750 per truck) and a rear rear is really easy to work on. as far as fixing your threads I would think there’s enough there to fix and definitely get a new nut. They really need to be fixed on a lathe so you can pick the right set of threads. Might be able to do it with a file I would say a threading die is likely to do more harm than good because it won’t know what thread to follow…and good luck getting one for 1.4x23 pitch or whatever craziness they are.

 

Don't need to save what is there. Watch this video from 20:00 - 24:00 mark. This is one way to do it. Or cut down with a lathe, weld to build back up, lathe back down and cut new threads.
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