Okay the other day I read on here about how your sides can flop around and your gas mileage is worse with the tailgate off. Earlier that day a guy who has his off said he gained two miles to the gallon and I said bull. Then I went back and told him that his sides might start flapping some. Now he calls me stupid but hes got a 97-98 f 150 can yall tell me why exactly it will start flapping. I need to tell this dumby why it is, I doubt he even understands what I say, though.

 

Dude his sides will not start flapping. It does bring down the gate to bed integrity somewhat, not to mention that a tailgate will cost many more dollars than he will ever save on gas when it gets damaged. You gain NOTHING having the gate down. Do a search here there is many a topic on the subject...

oh and welcome!!!

 

I haven't seen flapping bed sides in 20 years. They must have fixed these trucks. The only ones I ever really seen flapping bad were old farm trucks that had gone years with no gait on and they would overload the box and stretch out the sides.

 

Not going to flap my friend…

And, there has been many articles written about how you will NOT save any gas with the tailgate down…

I don’t have them handy but a search on the internet or even here on F150 will provide some information.

Another IMPORTANT factor about calculating gas mileage properly is you can NOT calculate it on 1 or 2 fill-ups of fuel.

It is best to collect data on 4 – 5 complete fill-ups with the tail gate down and then collect data on 4 – 5 complete fill-ups with the tail gate up.

I have personally done this and found for the overall best mileage as follows:

Best – Tailgate up with soft cover on bed.
Good – Tailgate up
OK – Tailgate down
Worst – Some kind of shell on the back as it creates the most drag on a truck.

Many things can affect your mileage with the biggest one being wind. You could have one of two really windy days and then many that are not. You will use more fuel on windy days if driving IN TO the wind.

A lot of people run one tank full and think they have some good data. Its useless as its not enough good data to arrive at an intelligent and accurate conclusion…

 

I agree with 01 here he is right on. bed cover is the best

 

I never drive with my tailgate down, Mainly becasue my bed is never completely empty.

I do know that I can drop my tailgate, grab hold of my bed side and flex either one side or the toher manually with little effort.

But if I put the tailgate up, I can not move the bed sides.

What happens is,
one; like mentioned earlier, the beds have been overloaded several times.
But two; a second way is with the tail gate down and the box only has 3/4 of it's sides. Then as the truck goes over bumps when the suspension is in the bottum of the bump and starts to rise the bed sides still want to be going down. (Newtons law: an object in motion wants to stay in motion) Gravity and physics work together to pull the bedsides down but since the structure of the bedside is convex for vertical strength and broke (as i nbent) vertically for horizontal strength. The energy is transfered out. Which results in the bed sides being pulled out. With the tailgate up, the two sides counteract each other pulling on each side of the tailgate.
With the tailgate down over time this constant flexing back and forth weakens the metal of the bottom corners of the bed floor to sides. It's like taking a piece of wire and bending it back and fourth, eventually it breaks.

For visual effect you can take a card board box hold it in the air and bounce it up and down. Watch the sides for movement. Then cut one end out, then again hold it in the air and bounce it up and down. This demonstrates the strength of a four sided box.

Then hold solid piece of wire and bend it back and forth notice how it bends easier each time and eventually it will break.
This deomonstrates the effect of the flexing on the metal.

1 week is not going to hurt it. Just displays owner igorance.
However, over several years it will hurt the truck and moves the owner to stupidity status.