Fastener assembly

A fastener assembly for use in fastening a cross member to the frame of a truck, comprising,

• a) a stud including,
• i) a head having a torque transferring structure and an underside wherein the underside includes a plurality of protrusions;
• ii) a shaft having a trilobular shape comprising a plurality of shaft elements having at least one solid shaft element and a plurality of outer surfaces, wherein the plurality of outer surfaces includes a threaded surface with a locking thread located adjacent to a Vee-shaped thread;
• b) a nut comprising,
• i) a nut body rotatable about the stud relative to the stud;
• ii) an annular surface on the nut body having a plurality of inclined faces oriented circumferentially forming portions of an undulating annular surface;
• c) a washer comprising,
• i) a washer body rotatable relative to the nut body;
• ii) the washer body having a bearing surface axially opposed to the annular surface and having a plurality of inclined faces oriented circumferentially and forming portions of an undulating bearing surface;
• and
• iii) a clamping surface wherein the clamping surface includes a plurality of protrusions.