Make pattern from print of Car by gluing to a piece of cardboard. Cut pattern to shape.
Draw shape on wood surface and mark axle centers.
Drill 5/16″ holes for axles.
Saw body from 2″ x 4″ lumber (sand sides smooth). Fill any voids, cracks or knot holes with filler.
Sand cut surfaces with a rotary sander to smooth.
Round over edges with ¼” router bit.
Sand edges to remove roughness.
Cut ¼” dowel to length (body + 2 x wheels thickness + 1/16″ or 3/32″ clearance). It is important to taper the ends of the axles to get them to easily go into the wheels. An easy way to do this is to gently sharpen the axles by turning the sharpener backwards in an old fashioned pencil sharpener-much easier than trying to do this with sand paper.)
Assemble wheel to one end of axle using white or yellow glue (Hot melt will not work.) (An easy way to glue the wheels to the axle is to dip a pencil point into a pool of glue and use the pencil to add the glue to the inside of the wheel axle hole.) Add second wheel to complete assembly. Test that wheels turn freely.
Rub your hands over the entire vehicle to make sure there are not sharp edges or points. Remove with sandpaper if any are found.