http://sitemaker.umich.edu/um.gm.truck

 

I went on a 200 or so mile trip last weekend, and left my tailgate down on the way there, and up on the way back. Got 23.5 mpg going, 23.0 coming back. First time I've left the tailgate down in a loooong time, but might try that again on longer trips. Had fun watching the mpg display.

 

there are still variables like elevation change and wind direction/speed that can affect mileage that much

 

There was a test conducted on Mythbusters to prove this very point. They used two identical new model F150s (relax, their test, not mine) and emptied the tanks dry. Filled them up to the top with the same amounts of fuel, and hit the road.

Both vehicles, same road, using cruise control....vehicle with tailgate up got about 15 or so miles further down the road.

It was stated (and proven) years ago that designers where using wind tunnels to design these trucks (from about 93 or so on). The way they are designed is to create a low pressure vortex in the bed with the tailgate up so that air passing over the cab will also pass over the vortex.....creating better airflow and little or no drag from the tailgate.

They showed this on the show too using hydro dynamics and scale models of the trucks.

There are people that will swear to this day that having the tailgate down will save you fuel. My reply, sure.

But I would just assume have my tailgate up, and not have to worry about some bozo hitting the tailgate while it is down. Heck, people have a hard enough time missing my hitchball.

 

Six of one, half a dozen of the other.

Mine stays up.

 

I hope you hand calculated the mileage. The display usually doesn't mean squat.

 

Anyone do a test on how long your taligate last while being sandblasted by all kinds of road debris?

Mine stays up too.

 

Heh. Thats why you need a pintle hitch on the back.. so that tailgater gets it right in the radiator ;p

 

Yep, agreed....that is why I have this....



.....mounted on......



I leave this on when I am not towing my big trailer. They need to make a pintle with a 2 15/16" ball.

 

Watch your tailgate during a light rain and you will see that it does not get wet when driving down the road.

 

" STUPID BADGE " Thats the 'U' shaped dent in the top
of the tail gate, Lot's of them here in the South....

Or is that a secret aero dynamic modification.

 

or just get a flow thru 5 wheel tailgate,i liked the looks of mine so i left it on and i swear i get better milage,not as strong as a regular gate as i bent it a bit loading the quad but works well

 

The pintle hitch does work well on offending bumpers, I personally busted a hole in my wife's new subaru bumper with my pintle. Stupid little pedals were so close together that I stomped on the brake and gas at the same time and backed right into my hitch.

I usually just leave the tailgate up anyway, too many beer cans and empty shotgun shells would blow out onto other traffic if I didn't.

 

I have the same problem...

Is it just me or have we had a lot of tailgate up/down threads lately?