I'm taking my truck on a long, long trip and time of arrival is not a factor, so i'm curious if anyone has the answer to my question. Is there a speed that is "MOST EFFICIENT" for a 2006 f-150 4x4? I looked through the postings and couldnt find anything.

Thanks for any help you can give me.

 

I don't know if there's a specific one for that truck, but I do know that on most vehicles, 65MPH is the most efficient speed. Basically, don't gun it, don't carry unnecessary weight, keep your tailgate closed and if you have one your bed cover as well. Use overdrive the entire time unless it's shifting back and forth too much on hills and whatnot. Use cruise control unless you're in very hilly areas, in which you'll want to let the truck slow down if it has trouble keeping speed going up hills. Keep your tires inflated to specifications, it might even help if you go a few psi over spec. Keep your fluids maintained, etc. There's other stuff that would help but would cost money to fix if you need it, such as tire alignment and balancing.

That's all I can think of...

 

Probably around 45mph in 4th gear.. ie, at the lowest rpm in the highest gear.

I drive without my spare tire. Every 400lbs of weight shed supposedly gains 1mpg according to the user manual. Plus, I get better performance since that's 100 fewer pounds of mass I have to accelerate every time I step on the gas.

 

Reading other threads about f.e., if you keep your engine rpm below 2000, you can maximize your economy.

 

My experience is if I keep it between 45 and 50 it gets significantly better mileage than 55-65. On flat ground at a constant speed I can get 22 mpg all day long with my '06 F150 4x4 5.4L 3.73 gears, stock 18" tires inflated to 42 lb.

Dale

 

When time permits and as do road conditions, I have found that the most efficient speed is about 70 km/h or 45 mph. At that speed, my truck runs about 1150 rpms, in 4th gear, TQ locked. As long as there is no big hills, I can idle around and I bet any money that I get over 25 mpg. I have never tested the actual mpg, but I do know a tank of gas lasts A LOT longer. I should try to test this sometime soon and see what the results are.

 

And how much fuel can you purchase with the $150 tow you will have to pay when you blow a tire?

What about the 1-3 hours of your time wasted waiting for that tow to a tire shop as opposed to changing it yourself in 20 minutes?

Sounds like gambling lots to save a few pennies.....

On the original post...

What said above is correct, the lowest speed your truck will go while locked into OD, which is between 39-45 MPH depending on tire size and gearing. That, however is NOT a safe speed on the highway, this causes accidents!

NOPE!!! Get in a car that will calculate and display MPGs...idling around will give you single digits... every revolution your engine turns wastes a certain amount of energy...talkes lots of energy to overcome friction, open and close valves, compress air, and at IDLE pump air through your throttle body. Your engine is extremely inefficient in low gears...on top of the losses through the torque converter while idling around. Veery inefficient!!!

I'd recommend about 55-60 on the highway if you want the absolute best your truck will do, while at the same time staying safe!

 

Since time isn't an issue...15mph will give you the best fuel mileage...I'm kidding.

I drive to Denver every other day from Fort Collins. At 65mph, I'm getting the best I've seen according to the computer. I've got a 3.73 axle, 5.4 Screw.

 

uh, just over one full tank at today's prices, and one tank doesn't last long :-( But I have free towing covered under my insurance :-)

Of course, one must know when and when not to drive around spareless...there are calculated risks :-)

I'll bet most blowouts are due to underinflation from neglect. Notice everytime summer begins everyone starts getting blowouts all over the freeway? Tires lose air over time. Riding on underinflated tires heats them up more than otherwise. Add to that a hot pavement to make the situation worse...

Plus, some study said for every 1lb psi drop in tire pressure on all 4 tires costs you 0.4% gas mileage. So if you're 10psi underinflated, that's 4% less mpg

 

You're dead right on that one! Keeping 'em inflated is key to long tire life. But...for all that self destruct from improper inflation, there are still plenty that go from other road hazards.

A calculated risk, I guess