Improving a box cargo trailer

[Frank Lee]

IMHO going after the fenders first is not the most effective course. The big dog is that trailing wake and you need a tail like the semi-trailers sport now. Next up would be minimizing the tow vehicle/trailer gap although I must say the trailer already has adequate radiussing on the leading edges so v-fronts and whatnot probably don't help much. I was thinking along the lines of shortening the hitch if that isn't too much trouble and if it doesn't result in trailer/car contact when maneuvering. Belly pans sure sound appealing but it seems the benefits are minor, especially compared to the work of fabbing them up. VGs and such- forget 'em, I think those also go in the category of either don't work at all or don't do much at all. Lastly I think you could relatively easily fab up some fender skirts from sheet aluminum or coroplast that could help that area out; I'm picturing something that looks like the fender flares on a 944 Porsche except with no wheel cutouts- fully skirted.

[mallrat]

In my experience, Airtabs work as advertised especially on big boxy shapes. Went from a consistent 30 mpg to a consistent 32 mpg on my 88 Honda Accord with no other changes, and I've talked to many truck owner/operators who have the log books and IFTA numbers to back up their claims of 4-6% improvement in fuel economy. Running the miles that they do, it adds up pretty quick.