In 1988, the 22R-E engine was joined by an optional 3.0 L V6 engine, the 3VZ-E. This engine was significantly larger and more powerful although not as reliable as the original 4-cylinder offering. Trucks sold with the V6 engine were equipped with the same heavy duty rear differential that was used in the turbocharged trucks, as well as a completely new transmission and transfer case; the transfer case was chain driven, although considered less rugged, created less cab noise than the old gear-driven unit used behind the four-cylinder engine.