Hello Joe, sorry west coast here so a little behind. Yes this cap is available , we invented it about a year ago and have been working on patents and production. But it is finally ready and you can check it out at home.thetruckmullet.com

IM me for more info

 

Hello, cap is secured by 4 or more API clamps resting on 2 inch wide weather stripping and in it's current design is not meant for opening. By it's smooth shape the aerodynamics is maximized, much like what is studied in that awesome aerodynamic study that Fastskiguy posted

We are planning on adding one or two designs that incorporate clam shell style openings or split hinge options. There are some interesting ideas we are toying with access from the rear cabin with shelving space in that upper curved section.

But yes for now it's fixed position cover.

 

I consistently get 17-18 mpg with combined hwy city with my 2010, 5.4ltr.
Best ever was 19+ on all hwy driving so can't complain.
BUT I wouldn't trust the onboard readout. In my case, it consistently indicates more than 20% better mpg, than what actual calculations of gas used to miles is.

 

My 2011 Scab FX4 Eco with 3:73 gears gets 20-22 on the highway going 65. In town it drops to about 16 depending on how many red lights I hit. I have Michelin ltx m/s2 tires on 20 inch rims and a tonneau cover. I cant ask for much more!oh and thats by hand calculations by the way! Computer is usaully off bu about half a gallon less than what i really get.

 

I've used two tanks of fuel so far, but I am averaging 13.1mpg in 100% city stop and go driving. I have the 5.0 v8, and this is right about what I expected I would get for mpg.

 

Heh, after a winter of, let's be honest, ****ty mileage conditions I had a 40 mile out-and-back run today. Headwind out and tailwind back, no traffic so I wasn't in anybody's way, and a freakishly sweet return leg!

 

Unfortunately, my daily driving consist of me driving less than two miles to work and two miles back home so my "city" driving suffers pretty bad. Truck doesn't even have time to warm up. 13-14 mpg avg. Luckily, it's not always that bad. Went on a 350 mile trip going threw several towns, stop signs/lights, and highway speeds up to 75mph. Averaged 20mpg the whole way.

Crew cab
6.5' bed
4x4
Magnaflow muffler
K&n "cold air"
5.0

 

I'm sitting at a solid 12-12.2 around town with my 2004 Supercrew 5.4 4x4 with a 4" lift and 33's on it. This is according to the cluster so it's probably not that accurate.

The car I got rid of for this truck got 10-12mpg around (AMG Mercedes) and my Durango gets about 12mpg as well. I am no stranger to horrible mileage. At least I have a supermoto that does 45mpg while beating the **** out of it. I also only live a mile from my work and might have to venture 20 miles away at most for ****. Mileage isn't a big deal for me at all.

 

If I am going downhill with my foot off the gas and I reset the fuel computer it says I am getting 99.9 MPG in my 2013 FX4 screw Eco

 

Great Strategy for better MPG'S