Abstract: A power transfer case for a four wheel drive land cruiser is altered to provide overdrive capability. A main drive gear is journaled for rotation about a main drive shaft driven by the vehicle transmission system. The main drive gear includes an axially extending hub section. A direct drive gear is splined onto the main drive shaft, as is an overdrive driving gear. An overdrive idler gear provides a mechanical speed advantage and is engaged with an overdrive driven gear that is journaled for rotation about the main shaft. A shift collar is splined in continuous engagement with the hub section of the main drive gear, and is longitudinally shifted to alternatively effectuate splined engagement with either a direct drive gear or with an overdrive driven gear. The vehicle is provided with four wheel overdrive drive capability without axial relocation of any of the major structural drive line supports or assemblies.