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MPX Update, Part 1: Aerocap Finds Free Fuel


MPX (Mother's Pickup eXperiment) deserves its own header, and mixing MPX with MAX is confusing (even to me) so I'm calling this post MPX's first update. You can read the MPX project overview here.


Here's MPX (Mother's Pickup eXperiment) on its way home from the MOTHER EARTH NEWS FAIR in Seven Springs, Pennsylvania. I had just crossed over the Oregon border when I took these photos, and as you can see it was taken last year. How can you tell? Because it isn't raining.

Yes folks, we're currently celebrating the annual Oregon Rain Festival. We don't have the least pleasant winters in the country—not by a long shot—but our winters are serious enough to interfere with testing. Mileage when it's cold and wet and windy is significantly worse than mileage when it's warm and dry and calm, and if there are rules of thumb for “How much worse is it, Jack?” I sure don't know them...but summer-and-winter are apples-and-oranges when it comes to comparative fuel economy testing. And so, for now, we have to rely on last year's preliminary test data, but that's enough to show that this streamlined bed cover gives a good bang for the buck. I can't be precise yet, but over-the-road fuel economy has gone from a smidgeon (see what I told you about precision?) under 25 MPG to within spitting range of 30 MPG. That's like finding a gallon of free fuel every 150 miles or so—Free Fuel In The Wind, to quote Phil Knox. If that doesn't impress you, think of the savings over the life of the vehicle: if MPX's first owner streamlined the bed the day it rolled off the showroom floor, it would have saved well over a thousand gallons of gas by now.

Which ain't bad for a DIY plank-and-plywood bed cover, which you can crank out in a week of evenings for around $125 in materials. It also offers most of the features you expect in a bed cover, such as keeping your possessions dry—and with the addition of a hasp and padlock, keeping your possessions in your possession.

This is not exactly an aerodynamic breakthrough. Lots of eco-modders have made their own (enough that there's a generic name for them; they're known as “aerocaps” among us high mileage zealots) and they average between 12 percent and 15 percent in claimed highway mileage improvement. It makes you wonder why you have to Do It Yourself...if they're that great, why aren't aerocaps commercially available? We'll have to get into that in another update.

Check out the 100-mpg car page for all Mother's MAX stories, and Kinetic Vehicles to make your own Max.

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1/17/2016 11:46:23 PM

Can you provide the details of your aerocap construction? Have you had time to make any other mods to achieve your mileage goal? What do you think of the scan tools that plug into the OBD port to check for MPG? I have an unmodified 99 Taco and regularly get 27-28 MPG and would like to increase that to ~35

3/25/2015 10:17:08 AM

While I understand your desire to not spend the money, although you can pick up a new diesel closer to 28k, if you drop the fancies, at least then you have something that can haul something safely, and stop with the load it is hauling. Your top photo is neither safe nor able to stop with the load you have it subjected to. To answer your question about why pickups moved toward more power and more payload, it is simple, working it their job! Yes, some people just buy them for toys, most however are sold to people using them for work. Ability to start and stop a load safely is one of the primary reasons to have a full sized pickup. While small pickups have been dropped, it is really the fault of the buyers. No buyers, no sales demand, no small pickups! That simple. Attempting to make a high mileage pickup, one that will haul basically nothing, is questionable at best. Doing it as a lark makes some sense though. Doing it safely, that should be the primary goal. Your photo shows safety is not high enough on your list. Your response shows you are not willing to address it either. As I stated before, any canopy will help the mileage some. With a regular one, at least cargo can be hauled in a reasonable manner. It would be more interesting to see what the difference is between a regular aluminum shell canopy, which can be picked up for less than $100 in your area. Also, VW diesels are also available, for around $2000 in your area, getting the 45 miles per gallon already. Much better toy to attempt to wring a few more miles out of too. After all, if this is about mileage, start with a great mileage machine first. Something Toyota has not been know for in their pickups.

3/18/2015 5:54:19 PM

Patriot1st, I'd love to be doing this project with a $40,000 Ram 1500 EcoDiesel HFE V6 pickup instead of an $800 gasoline banger with a couple hundred thousand miles on the clock--I think it would be twice as good a truck for only 50 times the money. But you know what would really impress me? If my Dodge/Ram dealer offered a $30,000 EcoDiesel with four (or even three) cylinders and 45 mpg on the highway, even if it had half the horsepower, half the payload, and a tapered canopy* instead of the HFE's cool trifold tonneau. There's no technical reason that 21st Century light truck manufacturers can't match the mileage of the most thrifty pickups of the '70s and '80s, but the pickup market has gone another direction since then. *Yes, really: a tapered canopy gives a big mileage boost, and I think the Ram HFE line would be particularly well served by it.

3/13/2015 10:38:46 AM

Okay, outside of an obviously dangerously overloaded pickup in the first photo, lack of steering, stopping and on the verge of axle breakage at the first large bump, not sure what you are attempting to show there. As for the big mileage boost with the tapered canopy, really? Just about any canopy is able to help with mileage on a pickup, and when I had one on my '87 Ford Ranger 2.0 liter, I would average between 27 and 31 miles per gallon no matter what the weather was like in the Willamette Valley. So what I see is you are getting into the same region of mileage that has been available all along, but not with a canopy/cap that will hold much of anything. Also, a regular canopy with a lumber rack on top, can be used to carry lumber or plywood at the same time as hauling other items in the bed. I also traveled at normal highway speeds for Oregon while achieving this mileage. If a person wants to have a great mileage pickup, the Dodge 3.0 liter diesel posts 29 miles per gallon, is safe to drive, and will haul a serious load at the same time. I am sure a canopy on top would be able to push it over the 30 mile per gallon mark. I am not pushing Dodge, but seriously, it is safe, can haul over 9,000 pounds of cargo, and gets outstanding mileage for a full size or any sized pickup today. The mileage leader of "pickups" was that old VW Rabbit diesel made back the late 70's, early 80's, 45 miles per gallon. Had a friend that had one, would regularly get over 50 miles per gallon. Could not haul much with it, but then with that sloping cap, not much will go under it either.