Numbers dont lie.

Skirts work. I know if I see a nice pair of legs, I slow down. Instant savings.

 

I had 240k on my singles when I lost that truck, thats OTR flatbed, but the company did get rid of singles. Fuel savings #### sure wouldn’t amount to enough to justify them, the amount of weight you save is what can be helpful. By the way, I like my duels

 

That's the only reason I could see companies using them. So they could scale 45K in a van.

 

You might have to ask nussbaum, they put every (supposed) fuel saving device on the market on their trucks including the flaps over the tandems.

 

This is exactly right. Their rolling resistance sucks on anything more than a light-ish load. Above medium load efficiency is lost compared to duals. The accountants only looked at purchase and replacement cost, and said #### it regarding fuel and downtime costs.

@DUNE-T Skirts work. But only on the macro scale. Roughly 10% reduction in drag will result in about 5% fuel savings. They don't work when the driver doesn't own the skirts, and isn't paying for fuel. Most of the drag actually comes from under the vehicle, after the air wraps back around from being pushed up and out from the front of the tractor.

The skirts keep it moving back on the clean(er) sides of the van, and not swirling up into the (aerodynamically) dirty undercarriage. Think fixed-undercarriage plane vs one with retractable landing gear.

That's the reason fairings exist. That gap between tractor and trailer actually sucks the air down behind the tractor and under the trailer. The top of the trailer is clean. They don't push air away from the top so much as they blow it over the gap, and it hits the clean/flat top instead of vacuuming down to the undercarriage.

Sorry if I'm saying #### you guys already know.

 

It'll only take one blowout to eat all the money you saved on fuel with super singles.

 

Not only do you have to buy a new tire but a wheel to go with it.

 

The bean counters really eat up any ploy to save a drop of fuel. The couple of gallons saved because they castrated the truck down to 64 mph got burned up by the hours of idling and lugging hills.

 

Hell, I can scale 45K in a reefer if it's loaded correctly. With 18 wheels.
We moved away from singles because of the blowouts...even with pressure monitoring, I had two separate internally with over 6/32 tread left. Pressure monitors saved me from a blowout...but still needed a $800 replacement and a road call

 

And you're going to have a difficult time limping to the nearest tire shop so you'll have a nice service call on top of it.