More mileage. with shell and without?

[gunz]

I dont know, but it seems to me the cap would cause the same swirl behind the truck that the cab causes in the bed. Seems to me tailgate down/removed should get better mileage.

i dont really trust the mythbuster test method on this test either.

 

[sle2115]

I must have saw the same episode sle2116 spoke of, as I remembered seeing it somewhere.


I also read a magazine article somewhere that shot down the tail-gate-down myth; mileage was actually a bit better with the tail-gate closed.

They even did a comparison with one of those open nets versus a closed tail-gate and the closed tail-gate won again.



I am sure that results would vary between body-styles and some makes might have opposite results.




As for the topper, I doubt one would notice fifty-cents a week either way in the real world.


It is worth a lot in rain-soaked Kentucky to have a dry place to haul feed, groceries, Christmas presents, and such.

Yep, that was the episode. They found tailgate up, open was better mileage than any other way...who knows. I too like to have a dry space for hauling and such, but on my flat bed, not much I can do...except drive the SUV!

 

[sle2115]

I saw the Mythbuster's test and think their "research" is not reliable or long enough to be meaningful. I had previously heard of the bubble idea, you can see it when you drive off with a bed full of leaves.
Nothing beats the results of someone who has driven thousands of miles both ways with the same vehicle over the same roads.
As for the weight of snow, not a bad thing, but the dog would prefer to ride under the shell. I put 4-6 sandbags full of gravel in the back of all our vehicles for winter, but not sure yet if this 3/4 ton will need much more than a full rear tank for traction. Spilled gravel is easier to clean up than sand and can be used for traction.
We are discussing driving it 1000 miles to Colorado for Xmas, Vs the wife's Cherokee, I think the truck may get better mileage when both are loaded, but too soon to tell.

The weight of the cap will help with traction too. I know my 87 in it's original configuration (factory bed, open diff) was horrible in 2wd in snow, adding the 7X9 flat bed helped, DRW helped, but the limited slip was the best change I've made in the traction department.

 

[MIDNIGHT RIDER]

I too like to have a dry space for hauling and such, but on my flat bed, not much I can do...except drive the SUV!

For the vast sum of ten bucks, I bought an old beat-up HUGE tool-box that used to be hanging under a flat-bed semi-trailer.

I straightened it out as best I could.

I welded two runners across the bottom with tabs/bolt-holes for four bolts that thread into tapped holes in my steel flat.

I welded a stout bar lengthways across the top with a loop in the center to hook my bed-crane/hoist into.

I painted it black.

It is water-tight and has a stout keyed lock.


I can quickly mount it on the truck or set it off with my hoist.


I have hauled many a sack of horse-feed in it and use it for weather-tight lockable storage when on shopping trips and swap-meet runs.

It has proved to be quite handy.

 

[DragRag]

If you want better mileage definitely go with the Tornado Fuel saver! Inflate tires to max psi, run a topper in conjunction with 3.55 gears I guarantee you will get 22mpg or better! Works every time.....

 

[92F350CC]

Makes me wish I had checked mpg after taking the shell off of my truck, even though it's a gasser. I gave up checking my MPG years ago in the thing, so I can't remember what it got really. I miss having the dry space to keep stuff, but it sure is a lot easier now to hop up in it.

I remember seeing that episode of Mythbusters, but I do not recall them trying it with a cap or cover on the bed. I only remember the tailgate down vs. tailgate up test. I've only ever driven with the tailgate down if there is something in the back that is longer than the bed, or if my registration is expired and I don't want the plates being in easy view.

 

[Arborigine]

If you want better mileage definitely go with the Tornado Fuel saver!

Now thats funny! I have seen old ads with identicle magic swirlys from the 1920s. I found one on my 1924 Willys-Overland and got a nice price for it on Ebay!
Modern engineers do through things like 3 or 4 vale heads, combustion chamber shaping, and combustion pre-chambers like an IDI engine.

 

[snicklas]

To be honest, I have driven all 3 major types of full-sized "trucks", in different configurations. I have driven piuck-ups, vans and mid, and full sized SUV's. The trucks have been open, 2 and 4 wheel drive, 1 with a "topper" (midwest name for a truck cap), and it also had a soft tonneau cover on it. 2 different full sized vans, a 5.9 Durango and my 6.0 Excursion. 2 of the trucks have only been driven with an open bed, a 73 F-250 2wd RC 390 V-8 and a 97 F-250 EC 4x4 5.4 V-8. These 2 trucks have gotten 15 and below for mileage. A 3rd truck an 83-F150 4x4 RC 351 V-8 was close to the same, this truck had a topper, and a tonneau cover. It was driven in all 3 configurations, alot, topper, tonneau cover, and open. Not much difference in economy between the 3... 2 E-150 Vans, 2wd, both customized vans, both with 302 V-8 (one carb, one EFI) and these would get consistently ~ 15 with a high on a long trip of 18. A 2000 Durango 4x4 360 V-8 and the best it would do is 13. And my 03 Excursion 4x4 6.0 PSD will get ~ 20 on the highway on a trip. I agree with most on here, it is not the configuration of the vehicle that gets economy (if you think about it, a truck with a topper, an SUV an a van are the same basic shape), it is the configuration of the gearing, power plant, the drivers right foot, and weather conditions. For 1 holiday trip, topper or no topper, I don't not think you see enough difference in economy to matter. The speed, gearing, weather, weight of the truck, and how hard you drive it will matter more. If you were wanting to hypermile, all the time there are things you can do to help. There is a guy that lives in the same town that I do, I believe his name is Dave Sopnagle (not spelled right) that has been on different boards and does hypermile with his truck. He has a 99 F-250, 2wd, RC 7.3 PSD. He has changed the rear gear to a 3.08, has changed the mirrors, has the truck sitting as low a possible, stock, he has made a cover, that surrounds the cab, and tapers down to the tailgate, he has put a "fairing" on the front to bring the nose closer to the ground... and he gets mid 20's..... but it has taken alot of work to get there...... I would say for a holiday trip, put the cap on it, and enjoy the clean, dry bed to haul your luggage and gifts in.

 

[RLDSL]

With these monster engines and heavy trucks, it's going to boil down more to gearing and driving style anyway. My truck weighs a bunch more than most on here being a CC with a Western Hauler bed , and I run around with a car top carrier on the roof all the time so I have some place to poke groceries and such when we are out, and the thing still gets 18-20 mpg running empty, but it's all in the gearing and the foot. Before I put the brownie on there for the double over, best I would get was 14 and now I can get that towing, but even running empty, that 18-20 figure only comes true if I keep it under 62 mph. If I want to run 75 mph, I can sit there and watch the fuel gauge go down.... and I don't have any tailgate, or sides to add to the equation, the hind end of my rig would probably be aerodynamically pretty darn close to as good as it can get, but that big roof carrier doesn't seem to effect anything. There's a lot of rolling mass there to begin with.

It's kind of like how they tried to convince big truck fleet owners that those pointed nose semi trucks got better fuel mileage, then after a few years come to find out , they were just trying to ease the pain into future safety regulations that required forward visibility within so many feet in front of the front bumper which would require slanting the hoods and the slanted hoods actually had zero effect on fuel mileage

 

[3/4 Ton-O-Fun]

Has anyone noticed the "flaps" of material that most of the trailers have under them and that some have at the back? I am thinking about rigging something like that up for the back of my camper shell/bed. I can't make my truck any uglier!

 

[RLDSL]

Has anyone noticed the "flaps" of material that most of the trailers have under them and that some have at the back? I am thinking about rigging something like that up for the back of my camper shell/bed. I can't make my truck any uglier!

Yeah, those look like something to be sold to fleet owners who have never driven a semi in attempts to convince them that they will save money with the things somehow... while the drivers shake their heads after the dispatcher chews them out for not being able to put on that extra couple of hundred pounds payload because of the things, then the driver gets chewed out for tearing them up trying to get into an impossible old place where he HAD to climb over things to fit that monster 53 ft trailer in and pealed the stupid belly skirts up. Just like the stupid side skirts on the sides of the cab that cut your turning radius , making it impossible to get in or out of certain situations considering those big trucks have to go into produce markets that were designed for horse and buggy
No owner operator in his right mind would buy that garbage for his truck. Those contraptions are sold to MBAs with ties that are on too tight and have no idea what a truck has to go through. You'll notice you always see those things on company trucks.
with the speeds your rig is running and the frontal area that it has, all the do dads on earth just aren't going to make all that much difference.
About the only things that do help any are add on nose cones for flat front trailers or cab roof top deflectors if your trailer has a flat front, but the cab top jobs only work on gooseneck or 5th wheel trailers. On a bumper pull they have deflectors that can mount on a shell . The nose cones do more than the deflectors in most cases and for occasional use you would probably never see a return on your investment for any of them.

 

[MIDNIGHT RIDER]

Has anyone noticed the "flaps" of material that most of the trailers have under them and that some have at the back? I am thinking about rigging something like that up for the back of my camper shell/bed. I can't make my truck any uglier!

I am gonna have to pay more attention; I haven't yet noticed what you speak of.

The only "flaps of material" I have seen are those black whiskers on the rear of UPS trailers and such that prevent powder-fine dust from permeating the door-seals.

 

[3/4 Ton-O-Fun]

These things are what I was talking about...

You must be registered for see images

RLDSL, tell us what you really think about the bean counters...

 

[MIDNIGHT RIDER]

That wouldn't last across the first rail-road track.

 

[Arborigine]

Well, that kills the only legitimate reason to even "lay down" a motorcycle.