Abstract: A selectively lowerable and raisable vehicle trailer system for raising and lowering of a vehicle trailer to expedite loading and unloading of cargo includes a rear wheel assembly. An elongated trailer is pivotally supported by the rear wheel assembly. The trailer is positional between a horizontal transport orientation and a sloped or angled loading/unloading orientation on the rear wheel assembly. The rear wheel assembly is selectively adjustable in position along the trailer between a rear transport position and a forward loading/unloading position, rearward and forward of the trailer center of gravity, respectively. A wheel assembly adjustment mechanism engages the rear wheel assembly. The wheel assembly adjustment mechanism operably engages the rear wheel assembly to facilitate selective positioning of the rear wheel assembly between the transport position and the loading/unloading position. A method of loading and unloading cargo onto and from a vehicle trailer is also disclosed.