I'm just about to put a toneau cover on my 2004 f150 heritage 4.2l. I've heard that the covers reduce drag and better gas mileage. Does anyone know just how much they better it. Estimates are welcome. Thanks.

mike

 

I posted my test results awhile back, but it was on the order of .5 mpg at 70. Adds up after awhile. You will not see any real difference around town. If there is any improvment, it's too small to measure.
Faster better for tonneau, unlike everything else...


My truck has a 4.6, Reg cab, with Brute Force intake, Magnaflow exhaust, Superchips tuner. Fold-a-cover tonneau, and about 200lbs worth of junk I have added to it since new (power seats, windows, locks, backup camera, heavier wheels/tires, etc. etc. etc.)

My best is over 24 on the road at the freeway speed limit. 22 is normal if I don't pass too many cars on the open road.
Around town all my mods work against me, and I have been averaging about 14.8-15.4.
That said, with my Superchips on Premium setting, and with a few new additions to my truck, I managed to get it down to 13.9 for this week. That's all local, and all fun driving. Very fun driving.
Chris

 

I was thinking of putting an aluminum tonneau on. I was curious about any gas mileage changes as the cover weighs about 85 pounds. My guess is that any gains would be offset by the weight of the tonneau

 

My Fold-a-Cover is aluminum, but it only weighs about forty or so pounds. I can carry it folded, but it's bulky enough that two people are better. A canvas one would give a better return for the dollar, but they sure are not as practical.

I think you will get better highway for sure, even at 85 lbs. Now some of these really heavy fiberglass won't get much improvment.
What model tonneau are you getting?
Chris

 

oops, I goofed on the weight, its only 68#. I'm considering this one

http://www.ltsportcover.com/tonneau-covers/F150-xf.htm

Do you have any experience with it or heard anything about it? I'd like to get some opinions before I pay 895$ for one

 

I have the Berlin standard cover on my STX Flareside and love it. Depending on your needs this cover is great..open the tailgate with it on, put on and take it off in the dead of winter without a hassle, and takes a beating in the winter with all of the ice and snow and still looks great and for cheap money as well. Like Chris, I will admit that the covers don't improve the mileage a heck of a lot. After reading Chris's reply the thing I have to do is look into one of those superchip tuners, if it makes that much of a difference in the mileage. Good luck with your decision.

 

I just can't justify paying 900 for a tonneau cover. I wanted to get one of the pace edwards retractable aluminum ones, but once again, I can't justify that kind of money for a tonneau. Even though I'd much rather have a nice hard cover, I'm going to get a soft roll-up tonneau for somewhere around 300 and just live with it.

 

I am sorry; I don't think I said the Superchips gives me better mileage. On premium it gives me worse mileage. OK, honestly, on premium setting, I can't keep my foot out of it, and neither can my wife, so that doesn't count.
The Superchips just makes it drive much better.

On gas mileage, the best for the buck was adding the K&N air filter. Cheap and I got a small increase, .25-.5 mpg.

The tonneau gave a reasonable return, but it's not on there for mileage, it's there because I use it as a big trunk. The mileage is a just a free bonus.
Still, if you freeway, you want a tonneau. My aluminum folding cover cost 512.00 bucks, and adding power locking (my install) cost another 5.00 bucks.
A fabric would be the best mileage bang for a buck. The undercover looks like a good choice also.

The Magnaflow helps the mileage on the freeway, does not help around town. It might hinder a little in town. Notice with all my mods I only get EPA estimate around town. Although my around town driving is not as begin as EPA tests, they test with few stops, low speed, etc.

I also live at 3500 feet altitude, high day temperature, cold nights, lots of hills, lots of stops. If I lived in a small town in Kansas I would be getting much better mileage.

The AEM intake gives me better wide open throttle power, but no better mileage. It actually gets less than the stock intake with a K&N filter.

The 5.4 has a lousy intake from the factory, and would almost always benefit from an intake swap. My 4.6 came with a decent intake, one Ford had pretty near perfected over the years.
So if I was looking for mileage with a 4.6 truck, I would start with a K&N, about 40 bucks, then a low price tonneau (If you drop a grand on a tonneau, you will never get your bucks back at the pump), then have a local shop put in a Magnaflow, or whatever, low restriction muffler, leaving the rest of the exhaust alone. The stock pipes are pretty big for a 4.6.
Do those three things and there would be a positive cash result.
The Superchips, intake, Catback, are there for power, and not likely to even break even on miles per gallon.
At least as long as gas is under 3.00 bucks a gallon…
Chris

 

Ditto. I paid 512 for my Fold-a-Cover but I needed to be able to lock it, and canvas is too vulnerable to a pocket knife.
The Undercover looks good, at 599 bucks at most places. The owners seem to love them.
The Berlin standard cover, like used by bobri, is very economical, and comes in a varity of colors for an extra twenty bucks. You can get one near your color for about 200, which is not bad for a non-black soft tonneau.

My local tonneau dealer could get me a Lund basic model hard fiberglass painted to match for about 650.

Lots of good choices out there.
Chris

 

I think more than one of us assumed it was the Superchip that was giving you better mileage. There's no way I can get anywhere near 22-24MPG. The EPA on mine is 17 highway, and it's only 19 for a smaller, regular cab RWD 4.6 STX, so that extra mileage has got to be coming from somewhere.

 

I used a Scangauge to 'learn' the best way to drive the truck, it also helps that I have many years driving a LOT of different cars/trucks/big trucks etc.

Then also notice I have a large vacuum gauge on the dash, Scangauge,etc. mileage is important to me. Honestly not for the cost, but because I hate waste of any sort.

I do seem to get a 'synergic' result from the tonneau, exhaust, etc.

Amazing enough, on one 120 mile test run, I had the truck up to the limiter 99-100 mph, for about three-four miles, and did a lot of high speed driving, mostly over 80-85 and got 20.

I could not believe it, and was waiting for the next fill up to show that I had not filled the tank correctly. Next top up after 180 miles at freeway, got 22. That's when I started to appreciate the freewheel design and super high freeway gears on these trucks.

Not so good around town, but great on the freeway.

If you don't have an instant mile reporting device, you are probably giving the truck too much gas at cruise speed, and you are probably using throttle to go down hill.

These trucks, unlike most vehicles since the old days of true overdrives, will freewheel, or coast down any grade. By only using the amount of gas pedal that the truck needs and by taking my foot off the gas earlier and letting the truck 'coast' up to stop signs, I really improve the mileage.

I am not talking about being the slowest car on the road, or even in the lower half.
The drive-by-wire combination with the freewheeling aspect add up to a strange condition where you can take your foot off earlier and not lose speed when coming up to a stop, or light. This also 'solves' the brake dust thing'.

Also, you can get different miles per gallon at the same speed. If you are going 55 on a flat road, you can slightly push the gas down, and still only go 55, but use more gas... That has got to be the drive-by-wire.

Going up a slight grade, you can use a lot of gas, or a LOT of gas, but not change the speed you are climbing by any noticeable amount.

Also the cruise on these trucks, due to the fact that unlike older cruise controls, is entirely computer controlled thus super accurate and really helps the mileage.

That said, I have not got the record for miles per gallon on these trucks. Several guys with only tonneau and K&N have broken the 24 barrier. Nobody seems to have quite got 25. Yet. Those guys cheated by only going 55 mph, and remember, that’s flat land, and no stops.
Chris

 

Just purchased an ARE fiberglass tonneau painted to mach the vehicle. Can't say if my mileage has increased since I haven't made any trips yet. It does provide nice finishing touch and a large lockable trunk. I do notice the vehicle rides a little better since the weight of the tonneau puts more weight on the rear leaf springs.

 

Hey Chris, I'm thinking of adding the Fold Cover type Tonnu. How long is your bed? Pictures look shorter than 8'.

 

Yeah, I have the 6.5 foot bed. Heck, I would have put a 5.5 bed on it if I could.
8 foot would be pretty long on these things. They sell em, so I guess they work out.
Look at the K-cover and the advance. All about the same. I think the K-cover has a better looking lock. Not sure.
Chris

 

http://www.amazingtruckaccessories.c...il?v=1&pid=223
K-covers on sale here. Take a look.
Chris