Ranger with a shed on top

[Interstatement]

My 1998 Ranger is my only driver. My truck needs require it to be nothing less than a giant multi-tool on wheels. To that end, I recently acquired an A.R.E. "Deluxe Commercial Unit" utility cap. It is already proving to be tremendously useful for my needs of versatile, locking, accessible storage. It's also proving, unsurprisingly, to be a huge drag on my fuel economy.

[Interstatement]

I used the aero template to get an idea of what to shoot for. Short-term plan is to fashion a deflector to sit atop the cab. Medium-term plan is substantial modification of the cap and building a front-hinged fiberglass box to deflect air and provide storage.

[oil pan 4]

Just don't put it on a lift with all that weight.

[Interstatement]

The other short-term goal is to cover the cap's roof rack with a removable smooth sheet of material to span and cover the busy grid up there when not in use.

Medium-term goal is to remove it completely once I've come up with another solution for carrying ladders and the like. That will likely be lower-profile longitudinal rack tracks with removable crossbars.

Long-term goal will be radical altering of the roof shape and structure above the horizontal drip rail/top hinge for the side hatches.

[freebeard]

Inappropriate use of The Template. You're dealing with a box not a teardrop.


https://unitimages.northtrailrv.com/...7246-p-800.jpg

Don't add frontal area. Seal the bed/cab gap as best you can.

[Interstatement]

Originally Posted by oil pan 4

Just don't put it on a lift with all that weight.

I don't know how much the cap weighs. I wish I did, but had no luck looking for weight stats on these. They were all built to order with many different options, so it would be tough to figure out without a scale.

While it definitely feels heftier than the cab-height fiberglass cap it replaced, the older gent I bought it from and me were able to lift it off of his truck and onto mine without help or undue strain or injury. The cap is built from 1x1 aluminum square tubing with .035 aluminum skin and a few aluminum extrusions forming the corners and hinges. My first deflector will likely be made from .040 aluminum, because I happen to have a decent-sized piece of it.

The curb weight of the 2WD Ranger Supercab is around 3,300 lbs, so I doubt it will even hit 4,000 lbs. post-modifications without a significant load onboard.

[ennored]

Originally Posted by freebeard

Inappropriate use of The Template. You're dealing with a box not a teardrop.

Don't add frontal area. Seal the bed/cab gap as best you can.

Exactly. Just get the leading edges rounded off. It's a lot like a box truck, square leading edges on the box are BAD.

Truck below (as been posted here before, but photobucket ate the images) is from a report you can read: Fairing Well. It's on page 29. Rounded leading edges reduced the drag by 30%.

[Tahoe_Hybrid]

Originally Posted by ennored

Exactly. Just get the leading edges rounded off. It's a lot like a box truck, square leading edges on the box are BAD.

Truck below (as been posted here before, but photobucket ate the images) is from a report you can read: Fairing Well. It's on page 29. Rounded leading edges reduced the drag by 30%.

they are using Square edges now on the rear..


it's proved to be more aerodynamic also better hood designs push the air from the top of the hood to the sides rather then over the top of the SUV.. I see this on my tahoe hybrid .. at lest that is what is happening to the rain water on the hood.. these are both 2008 models one hybrid and the other non hybrid

one 0.34Cd and the other 0.38cd

the square rear edges is standard from the 2015 model onwards

[kach22i]

FYI:
Old thread on a similar problem.

New and seeking aero advice for my "brick"

[freebeard]

Compare to the Airstream motohome. The roof cap has a shallow angle (like the Cybertruck) at the top edge and the edge radii behind the doors extend upward with the caps lower edge arcing upward as well. A Colani truck would be even more pronounced.

IIRC aerohead found no benefit to the raised cowl.