last launch we used in depere wi we didn't have to use 4x4 at all as the ramp was super steep(had '00 ford f150 triton). dropped boat in and rear tires never even saw water. ramps here at mead are not steep at all. rear bumper is in the water before boat a$$ end is floating. rear tires are in the water up to the axle and fronts are usually wet. 4x4 is almost mandatory.