kelticF150

Starting December 20th I will be moving from NY to Georgia to Texas to Oklahoma back to Georgia and then to Kentucky, all within the span of a year (gotta love the Army). Alot of highway driving and alot of it with a trailer probably. What do I need to do to optimize my gas mileage and protect/enhance my truck? (besides all the usual good driving tips, what types of mods and fluids should I look into?)
Also, I've been thinking about putting on a 2" leveling kit, should I just wait until I'm "settled down" a little?
I bought an 04 F150 5.4 FX4 back in May and love it, but the only modification I've been able to do so far is install a K&N 77 series intake (LOVE IT!). Thanks for any and all help, love this forum!

nvrenufedge

I would say a tonneau cover of some sort and exhaust. I have a soft tonneau, K&N filter, & Magnaflow dual exhaust (mild setup) and milage went from 13 city to 16 city.

hsv_mikej

Doubt the tonneau cover did anything at all for city mileage, but the other items could help.

There was a Myth Busters episode where they looked at the myth about mileage going up with the tailgate down, and in their test with the trucks they used the mileage went down with the tailgate down, since drag actually increased on the truck with the tailgate down. The same thing happened when they put a tonneau cover on the bed. They put a truck in a wind tunnel stock, tailgate down and with a tonneau cover. The best air flow around the truck was the stock configuration.

Franchi

I wonder why that is? I've heard of that show before but never seen it.
I studied aerospace engineering in school for a while before I switched majors and I am curious to see how with a tonnea it adds to it. POSSIBLY I could see with the tailgate down as it's elongating the vehicle air flow. I might have to look that show up and see. :-)

hsv_mikej

With the tailgate up there is a swirl of air that forms a "bubble" in the bed area this makes the air pass over the rear of the truck, with the tailgate down the bubble doesn't happen and the air rolls off the back of the truck and swirls around causing drag. If you do a Google search for Myth Busters truck tailgate myth, you can find some pictures and diagrams about the episode.

Franchi

Cool, will do. Thanks bud!

PawPaw

If you will be pulling a trailer I would wait on the leveling kit. Other than that you can use synthetic oil, keep tires aired up to the max, maybe get a programmer and exhaust. Most important is to keep speed down 55-60mph when towing.

dplummer87

I question their tail gate down claim though.

If you remember the episode, they used some tiny P.O.S. truck with a V6 that had like 3.0 engine in it...Not much power.

My dad drives a mega cab with the 5.9 cummings in it. He mad the same trips twice and tried one with the tail gate up and one with the tail get down. He went strictly by his overhead read out as he is to lazy to hand calc.

According to the overhead, with the tail gate up, he got an average of 19 for the trip.

With the tail gate down he was at 21.5...

I also have tried it with my 08 FX4 5.4 and by hand calculations I get better mileage with the tail gate down...

I really want my dad to try it with the tail gate off...(THe dodge tailgate feels like it weighs a 100 pounds!!!)

Also, my ex had a hard top on her F250 and said she also got better mileage with it that she did with the open bed...

I think the fact that the motor has more power it is actually has less problems pushing the truck on the highway with out the so called "air bubble" forming in the bed of the truck.

The little motor truck needs that air bubble as it is barely able to push itself to begin with...THoughts??? Any one else also feel they get better mileage with the tail gate up or down???


Get a tuner and exhaust man, let it breath, that extra HP with help you out on the highway.

hsv_mikej

Your dad's test would not be a valid argument since the trips were not made at the same time, speed, weather, and so many other factors come into play.



The tailgate up or down, which is better could be different with every brand, model, cab style, tire size, bug deflector, raised, lowered or anything else in the bed of the truck, it all depends how the air flows over the truck.

Some trucks may do better, some worse, but unless two identical trucks do the test at the same time nothing can be claimed.

And even with two identical trucks the test should be ran at least twice with the same two trucks but swapping the truck with the tailgate down. Just to validate it more, since no two trucks are ever the same. One may be running better than the other one.

The best you can do is just keep the truck running as best as you can, keep the tires inflated and drive smooth.

Eric85

My show truck s10 has a tonneau on it and improved the gas mileage with no other supporting mods by 2-3 mpg.

Only had the f150 for about 5 days now so no MPG readings on it yet.