[trace33chargers]

Why do you replace the nut every 4-5 uses? That is a waste. Just reuse it. The threads aren't going to wear out as long as you thread it on properly.

I'm 99% sure there won't be a difference in threads so the newer axle would work. Just know, you are supposed to replace a locking nut everytime it is taken off (not that anyone ever has done that). So you would be in the same place you are now.

Just run your nut you have now.

 

[trace33chargers]

Not having a cotter pin would be quite dangerous...

It could if the axle isn't tightened. Most, if not all nuts anymore lock themselves after tightened. The lead angle and friction are what keep it in place. But if some grease got in there it could loosen up.

So dangerous, but not as dangerous as one would think.