American 53'' trailers

[Fabrux]

Those bars are usually used in trailers that will be lifted from the sides to put on rail cars.

[Aerodyne03]

Ok, thanks, so I wouldn't wear them, no they look beautiful to me ...

[niteowl7710]

The aero side skirts, or underside spoilers are a requirement for trailers entering California.  As of 2012 any trailer operating with the state are required by the CARB (California Air Resources Board - they're the ones that came up with things like California Emissions, and keep forcing Tamiya to relabel their paint) to be equipped with aerodynamic devices such as cab fairings, side skirts, and trailer "tails" of sufficient design to garner a 5% increase in fuel economy.  Which for the average semi would be an extra 1/3rd of a MPG (7.38 vs 7.0) or so depending on the brand and model of the truck.

Edited August 8, 2020 by niteowl7710

[Aerodyne03]

Gone are the days when with a nice 359 and a fruehauf 
trailer that had the aerodynamics of a building with
 scaffolding you traveled to the usa smokey and the bendit style ... ?

[Aerodyne03]

Since we're talking about rules ... even if it doesn't 
have much to do with trailers ...
How are you put on the DEF? (In Europe we 
call it adblue, we pay 70 cents a liter and it falls
 into the hassle of a truck driver when he has to refuel ... ??)

[Fabrux]

On my Freightliner Cascadia it has a separate tank between the battery box and the fuel tank in the driver's side. Most fueling stations have bulk DEF/AdBlue pumps built in to the diesel pumps. The pricing is around the same per unit as the diesel these days.

I don't know of any kits that come with a DEF tank, however I know KFS offers them.

[Aerodyne03]

Wow, you drive a Cascadia, what would I not give here in Europe
 just to see one??, being a truck driver on the streets of the 
United States has always been my secret dream ...??

[niteowl7710]

 

I have a Cascadia too, right now down in Pennsylvania diesel is $2.79/gal, and DEF is $2.99/gal.  Only use a couple of gallons of DEF per day vs. 60 gal of diesel.

[Aerodyne03]

Nice day cab !!
Yes, even here, trucks don't consume much of it ... 
and petrol distributors sponsor it like this ...

[Aerodyne03]

On KFS I found this, it is an auxiliary tank from a scania
 but it looks like one for the DEF...

[Aerodyne03]

To get back to the trailers, I saw a video of the utility.
Why are the two door locking systems not symmetrical?
How does it work when they open?

[Aerodyne03]

[Jim B]

One door swings to the right & one door swings to the left.  When they close the overlap some to create a seal.

[Force]

Yes, if the doors overlap it doesn't matter so much where the espagnolette locks are, I have seen the ones in the pics above, one on each door, two on each door and two on one door and one on the other, so it's up to the manufacturer where they put them.

[Aerodyne03]

Ah, got it!??
Here in Europe it is not customary to overlap
 doors so much and for this reason I just didn't understand ...