Greetings from a diesel truck driver pulling a 5th wheel

[skyking]

Hello all. I realize that our hobby is not exactly a fuel sipping adventure, but I am interested in doing what I can to minimize fuel consumption.
I have built some custom wood boxes for my truck and will be building a new grille and bumper next. These trucks have excessive cooling air and that subsequent drag under many conditions, so I am building a louvered grille that will either be automatic or at least controllable from the cab.
After the hood and bed system is complete and the bathroom is remodeled in the house (gotta have priorities!), I plan on building a sophisticated air dam system. I plan on articulating it so it can be close to the front of the trailer and allow for turns.
I have it mostly designed in my melon, but wanted to learn everything I can before proceeding.
I also want to find out the benefits of belly fairing my truck vs the low skirt option that I see here.

[Daox]

Welcome to the site.

Cool ideas, would love to see pictures when they come to fruition.

[skyking]

Thanks! I'd show you pictures of the truck and wood tool boxes/sides, but photobucket is on the fritz.
I'll be building the roof air dam or fairing using stitch and glue methods from my boatbuilding past.
pygmyboats.com has some info on it. I can make a large fairing that will be natural wood finish in appearance but glassed over and protected from the elements. The whole truck is going to be a woody so I might as well continue with the theme.

[albyneau]

Welcome!

[JasonG]

A deflector will help some.
If the rear is rounded, squaring the trailing edge will help. I noticed this when I bought my toy hauler.
My next step is a rear Kamm spoiler.
Of course, run the tire pressure to sidewall max. You will have less sway as well.

[skyking]

Thanks Jason, good to hear I am not the only RVer here.
My 5th wheel is a 1991 model with less than ideal aerodynamics.
Here is a link to a pic, you may have to copy and paste it due to linking rules at that host.
http://pics.bbzzdd.com/users/skyking/coleman10.jpg

It is a slick side and the belly is relatively clean on it, which are both pluses. I figure with that sloped front if I can fair it from the top of the cab to about 70% up the slope and within 6" of the trailer, I'll see a significant decrease in drag. Now it is about 6' from the top of the back of the cab to the trailer face. Of course I'll be dealing with difference in width as well, the cab being about 5'6" and the trailer at 8'. Imagine a triceratops shield

[bestclimb]

it's good to see a truck get worked. How difficult would it be to fair the trailers wheels? you may also see a significant reduction in drag with a boattail. If done right you could add quite a bit of storage.

[skyking]

I was eyeballing the back for a Kammback or boat tail.
The trailer tires might be a chore to fair, since the surrounds on the far side are part of a slideout.
My truck is not the best by itself, with running boards and a harsh corner aft of the cab formed by my new wood boxes. No going back now, they are almost finished.
Truck as I purchased it:


After paint Saturday:



Wood toolbox sides under construction:

[JMac]

Welcome. I like the way you think.

JMac

EDIT: And thats a heckuva lotta clamps!

[JasonG]

The skirts will depend if your tires are inside of the slides wall or they stick out. If flush it will be easy to add a panel attached to the back of the metal that hangs down from the slide.

The full bellypan is a big help. I am adding a deflector to mine in front of the axle to direct the air under it before its next trip.