A secondary lock assembly for a fifth wheel, where the fifth wheel includes a hitch plate with a rearward opening slot to receive a trailer kingpin and a transversely sliding primary locking member for retaining the kingpin within the slot. The assembly comprises a tie bar pivotally connected at its middle to the primary locking member and a transversely oriented pull bar pivotally connected at an inner end to the forward end of the tie bar. The pull bar comprises a rearward offset tab. A latch is pivotally connected roughly at the center of the latch to the forward end of the tie bar, and also pivotally connected at a point rearwardly and inwardly offset from the first pivoting connection to the offset tab. A detent extends from a transverse wall comprised in said hitch plate such that said detent lies in the same horizontal plane as said latch.