A work vehicle may include a chassis, linkage, and locking pin. The linkage may include an upper link pivotally connected to the chassis, lower link pivotally connected to the chassis, and boom. The boom may include an upper arm pivotally connected to the upper link, lower arm pivotally connected to the lower link, front arm pivotally connected to a work tool assembly, and locking tab affixed to one of the front arm and the lower arm and protruding from one of the front arm and the lower arm in a direction away from the work tool assembly. The locking pin may be connected to the chassis and extend laterally relative to the chassis from a retracted position outside a travel path of the locking tab to an extended position intersecting the travel path of the locking tab.