Bad gas milage....help

True covers do not have any true improvement on fuel economy. Also any improvement would be dependent on the vehicle and the aerodynamics. I didn't buy my truck with fuel economy in mind, but rather my needs and functionality. I also have the Access limited rollup with no complaints.

Here is a study that was posted on a forum here in regards to fuel saving with a cover.

1) The largest reduction in aerodynamic drag (7.8%) was observed at 85mph. If we’re generous, we could assume that 75% of the engine’s power is being used to overcome the force of drag at this speed (the other 25% goes to tire friction, heat loss, etc.). If drag is reduced by 8%, that would result in a 6% reduction in engine workload. If the truck averages 18 mpg at this speed, then reducing engine workload 6% would improve fuel economy 1.08 mpg. SO, at 85 mph, expect to see about a 1 mpg improvement with a tonneau cover.

2) At a more realistic highway speed of 65 mph, drag is reduced about 5.5%. Using the same math as above but assuming that only half of the engine’s power is being used to overcome drag at this lower speed, fuel economy is improved by 0.5 mpg.

3) At 55mph or below, the fuel economy benefit basically disappears. Aerodynamic drag isn’t significant until you reach speeds of about 55-60 mph. Technically there would be a fuel savings, but it would be small. Less than a tenth of a mpg.

4) Finally, there were 6 different tonneau covers tested. SEMA didn’t disclose which was which, but we’re fairly certain that a fitted, over the rail solid fiberglass tonneau cover gives the best fuel economy results. The cloth/vinyl covers buffet in the wind, and anything that doesn’t go over the rail creates it’s own vortex. Painted to match, these covers cost $700 to $1100 installed.

Now before anyone goes off on us for making assumptions, etc., we did speak with a couple of engineers when writing this article. They emphasized these are rough numbers, and that they could be off by as much as 25%. That means that the best case fuel economy improvement is 1.35 mpg at 85 mph, and 0.63 mpg at 65 mph.

Assuming gas is $3.50 per gallon, here’s how the best case math works out:

Driving your tonneau cover equipped truck at 65mph for 20 minutes per day would save you 0.04 gallons of gas, or about $0.14 per day. Under these circumstances, we figure it will take about 30 years of workday commuting to save enough to earn back the cost of a $1000 tonneau cover.

Drive your tonneau cover equipped truck at 85mph for 60 minutes a day and you’ll save 0.33 gallons of gas, or about $1.16 per day. We figure that’s only 3 years and 7 months of workday commuting to earn back a $1000 tonneau cover. Of course, during that same period, you’ll spend over $13k on fuel. We feel sorry for anyone that has to drive their truck 85mph for 60 minutes a day — the fuel costs for just three years would be enough to buy a nice toy (ATV, boat, motorcycle, etc.).

Bottomline: Tonneau covers DO save gas, but not very much. While the aerodynamic drag numbers sound impressive (4-8% reduction), they don’t actually result in enough gas savings to justify the expense for a normal user. If you buy a tonneau, do it because it keeps your bed dry and secure.

 

I dont equate .14 cents, more like .05 cents with gas the price it is as a savings, but to eachs own.

 

If you read what I said, the speed limit here is 75. Most of the traffic is going 85-95. Going 65 isn't really an option. I'm asking what I can do in the constraints of what I'm doing. Obviously if I drive slower I'm going to get better mileage. And I won't be using the cruise control for a full tank to see what kind of difference it makes.

 

You can go 65-70 but you may get ran off the road.

 

That's what I'm saying. Even the semis are moving at around 70-75. If the answer is hey man there is nothing to do sucks to suck, that's fine I bought a truck I can afford the gas. I was just asking a question to see if there was anything I could do.

 

Keeping it under 3,000 RPMs is not driving like a grandpa. Keep it under 1500-200o RPMS.
Driving under 3,000 is just driving like any other person in the world who takes off at a green light.

Your gas mileage will drop past about 60-65mph. So going 75 you should expect to see a decrease in mpgs.

I keep my RPMs around 1500 or less ideally. I rev under 2000 RPMs and I don't drive over 60mph and I get 21 mpgs.

 

Im with ya, untill its realy broke in you realy cant change much. And where you preety much need to drive those speeds its going suck.