Ok while iam not new to owning a 5'er or pulling a load (haul Gas for a living with a tractor/trailer) i have'nt bought a 5th wheel Gate.

We've owned a 5er for about 3 years now (2009 Sundance) & never really pulled it more than a couple hundred miles but now that i live in NC & will be makin frequent trips to MI to visit friends/family (850 miles each way) iam wondering if leaving my normal tailgate @ home will help fuel economy in my Powerstroke.

According to a MythBusters episode & my own experiance a pick-up gets better milage w/the tailgate UP during normal driving, but a 5th Wheel really changes air flow.
In fact w/normal tailgate used while pulling, objects will float in box & can work there way out (i know this).

It seems to me a vented or removed tailgate would cause airflow to hit bottom face of 5'er directly & maybe decrease fuel mileage, so maybe the whole 5th wheel gate thing is just a convience so u dont have to remember to raise/lower your tailgate.

So my questions are
1. does a 5th wheel tailgate help increase fuel mileage
2. do objects still float in bed w/a 5th wheel tailgate
3. is it ok (either legal or safe for bed-sides) to NOT use ANY tailgate
Hopefully someone has info (experiance) on this both ways

 

1. No, the trailer is too close to cause air flow problems I would assume.
2. Never had this problem, but dont tow with a 5'er
3. Yeah its fine. No problems.

 

1. I would think the 5th wheel tailgate is just for convenience. I'm doubtful it would increase your fuel mileage.
2. While more air might flow out that way with a 5th wheel tailgate I dont think the area removed wouldn't be sufficient to stop things from floating.
3. No tailgate necessary. Last year when I was hauling the trailer every few weeks I just left mine off through the summer.

 

I would suggest in the overall scheme of things the impact of a tailgate either for or against fuel mileage would be negligible.

Steve

 

It's like most other "put this on and save fuel" devices - it won't save enough money to pay for itself over the lifetime of the truck.

I've got an electric Roll 'n Lock cover that extends back to just in front of the fifth wheel hitch when I'm towing. That smooths the area between truck and trailer so there isn't as much air flow down through the bed (light weight things don't fly around so much in the rear of the bed.) But I bought it for security of items in the front of the bed, not for fuel economy.

 

What they all said above. You definitely need to have things tied down in the bed when towing. But when not towing, I like my folding hard cover with my tailgate. Everything is hidden and and dry under there when not towing, and it folds up easily for towing.

 

Thanks for replys guys, i was just tryin to determine if its worth buying & storing a 2nd tailgate.
Probaly not unless i can get a good deal on a nice used one

 

Any airflow you can direct over the top or around the side is preferable. If you run OTR, you've noticed the new skirts that keep airflow out from under the trailer. A tailgate would accomplish the same thing. A cab mounted air deflector would help even more.


TURBOWING AIR DEFLECTORS from WINGMASTER COMPANY | StreetPerformance.com

 

I'm with RPM371 - prevent the air from hitting and deflecting off the face of the fifth.

 

I know what you mean, the turbulence in and around the inside of the pickup bed while towing a fifth wheel is pretty strong. There is a lot of air that gets directed in all directions under there. I think the best thing would be some kind of cover like a canvas boat cover, where you have snaps and you can seal the entire bed with tailgate closed.

I don't think anyone would take the time to do it but it sure would be interesting to have a canvas tarp that would snap to the top of the kingpin box and cover over to the bed rails. It would be a trick to allow for turning, but it would keep the air from buffeting around the bed.

Probably would get better results by installing a front air dam like they use on NASCAR cars, where there is a piece to bolt on the front bumper that gives you 3inches of clearance to the ground. This is supposed to gain us up to 3 mpg on interstate runs.

 

You could have a custom tonneau cover made, either tarp or fiberglass. It would definitely help with aero, but it comes with it's own set of problems. If you go with tarp, you have many snap holes to drill. If you go with fiberglass, it will have a gap in the rear. Lose/lose.

A cab mounted air deflector and closed tailgate will give you the most bang for your buck in the Aero Dept.

 

Those deflectors will only work if your driving directly into/with the wind ... a crosswind will negate most of the deflector's work ... the "dam" would have to be faired all the way back to the leading edge of the camper.

RPM371 mentioned the OTR skirts ... similar for the tail fairings, too ... idea is to reduce the eddies generated by the surface gaps.

As a matter of practicality, I don't know if sufficient fairing can be done between a pickup & a camper trailer to make it worth while --- you still have the maneuvering requirement.

Just my thought ...

 

And of course, all that deflecting stuff costs money. Will the amount you save in fuel be worth what you spent on the deflector and installation? For me, not likely. For someone who does a lot of traveling, maybe.

 

Just thought about something. A 5th wheel would cover most of the bed anyway (Vs a gooseneck or bumper pull). A bed cover would get you minimal aero advantage with a 5th.

True that the deflectors are most efficient in head on wind, but they do help in cutting drag. Big trucks have been using them for years. Crosswinds are going to kill you no matter what.

 

I use the 5th wheel tailgate but not for any fuel savings. I use it for the ease of hooking and unhooking. I don't have to lower the tailgate to get the king pin in the box, put the tailgate up to hitch the king pin and vice versa when unhooking. No risk of damaging my tailgate or the front of the trailer.

Might want to consider one just for the convenience.

S