The Hagelnut from Rather Engineering is an improved adaptation of the conventional three-piece jam nut used as the primary wheel end retention system in the tractor/trailer industry. Using the Hagelnut, a controlled amount of wheel bearing preload will have been installed to assure ideal running conditions. The Hagelnut wheel end fastener system is available for the standard trailer model axle having a 2-5/8 - 16 threaded spindle.