Ed
Even with a cotter pin, the ball can still come loose and waller out the stud.
Castle nut would be better.
But in my feeble mind, Lube the threads,nut face and torque to specs.
Remember, you are stretching the stud to keep it tight, not friction.
Sorry, my Nuke side is coming out.

Don

1967 GMC 9500 Fire Ladder Truck
"The Flag Pole"
In the Stovebolt Gallery
1946 2-Ton grain truck
1946 3/4-ton pickup,
1953 1-ton pickup
1957 1-ton flatbed dually,
1954 Pontiac Straight Eight
Of all the things I've lost in my life, I miss my mind the most!