How much torque should you use for the rear axle castle nut?
Between 40 to 47 foot-pounds is what you should be aiming for – we usually set the torque wrench to 42 ft/lbs, as if the wrench is off by the specified 4% we’ll still be within the torque range.
If the holes don’t line up properly for the hitch pin clip or split pin to go through, try tightening slightly – it’s generally best not to over-torque this nut as you might damage the spacers, so if you aimed for the lower end of the torque scale you should have some room to move whilew still staying within spec.