I realize that yours is a '37, but the '48-'51 Truck Shop Manual says to torque to 33 ft lbs, then back off 1/6 of a turn until the cotter pin will go through one of the two holes in the spindle. I don't have any idea if that would be what is called for for a '37.
The bottom line is, you don't want any drag, but you don't want any end play either.

1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission