|
My guess would be, lack of standardization of dimensions and shape. Trailers are typically the same dimensions with the same door design, so it's easy to market a product that will fit practically any trailer. To do the same for vans/SUVs, you would have to redesign (expensive) and manufacture (also expensive, especially in small quantities) a different mounting system for every model. Not to mention the extensive testing that would be required--Van A might achieve best drag reduction with panels of a different length or at a different angle than Van B.
|