At what speed do you get your best gas mileage? I know that the higher your RPMs the more gas you would consume, but you would also be covering more ground. I'm talking on the highway of course. Just something I was pondering..

 

I have always heard that the closer to 55 you are the better the MPG. My 4runner seems to get the best mileage around 60 to 65.

 

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Around here we are allowed to do 70 on the xway and most people do 75-80. If I set my cruise on my 2.7 Tacoma at 65-67 it really improves the gas mileage. Now that we are at $3.04.9 a gallon for reg. I do try to keep my speed down around town and highway. My biggest problem is having to climb these mountains all day long to go anywhere. The xway cuts threw the valleys and that helps but there are still some really steep mountains depending on where your going. Mike

 

I have a 95 4runner 4x4 3.0. I find that around 60-65 is best for me.

 

Ive been a competetive MX racer half my life and having a twin brother to compete with, I find that no matter what I do, I always try to do it faster than everyone else. This of course includes traffic, walking, tests at school, etc. Doing 65-70 on the highway just doesnt cut it for me, when someone passes me I get that very competetive feeling. Its almost an anxious feeling. Then the gas pedal goes down, I pass them back, set the cruise, and feel better. I end up getting about 17 on the highway, and aorund town.

 

I got ~21 mpg if I went 65-70 on the highway. 75mph set it back 2 mpg.

 

According to my scangauge the "sweet spot" on my 4Runner is around 60-65mph at 2100 RPMs. With prices on the rise I have been slowly letting my engine build speed up to overdrive and now am getting around 19 mpg rather than 17mpg from jack rabbit starts from redlights. The right lane has now become my friend.

 

So many variables like gearing, tires, pressures, filters, lubricants, mods that create aero drag, tranny type, elevation, etc. that no one answer applies IMO.

But, no matter the Toyota SUV, I've always been able to increase mileage on-road 1-2 mpg by removing 3rd row seats and the spare (Fix-A-Flat + AAA).

 

The spare tire is probably a good idea for me. It's the wrong size anyways. I've been one to think if I ever had a flat then I could limp home by putting the spare up front without worry too much about damaging the rear end gears by keeping the rears the same size.

 

youre going to always get the most miles per gallon when youre at the very BOTTOM of your highest gear. for us with 5spds that means as soon as you can shift into 5th and maintain that speed, you will be getting the most miles to the gallon. the 55 mph that a lot of magazines say and that some speed limits are set to corresponds to when a typical transmission shifts into the last gear. after that its just your RPMs going up within the same gear meaning using more gas (though more speed). other factors listed above definitely have an effect but gear-wise/speed-wise its where ever you can shift into the bottom of your highest gear (and maintain speed...i dont recommend shifting into 5th at 15 and trying to maintain that)

 

RPMs don't have nearly as much to do as throttle position.

Your fuel economy is a function of your speed divided by fuel consumption. There is a certain gallons/hour related with any vehicle speed.

The determining factor is your drag profile. Because of the v-squared relation it takes alot more power to push your 4-runner shaped parachute through the air at 70mph than at 60.

 

I've noticed when i'm going over trails at 10-15mph, i get about 12-15mpg.....faster, at 60mph on the highway i get 22-23mpg, kinda wierd

 

I should have clarified. by "maintain speed" i meant with any normal amount of accelerator position and not flooring it. the 55mph on some freeways and that you read in magazines certainly does come from having your engine at lowest RPMs while being able to maintain that speed without flooring the accelerator.

 

My best mileage is when the keys are in my hand and my 4runner is in my driveway. My mileage is never pretty at any speed.

 

Believe I read somewhere that your best economy is at peak torque in your higest gear.

 

At 55mph you will get your best fuel economy/miliage. Yet anything faster you will lose your fuel economy fairly rapidly. I think they say was that you burn 25% more fuel at 70mph than at 55-60 mph

The spinning("unsprung weight")Tire and rim weight, and tire rolling resistance (tred) has a Large impact on how much fuel your engine has to use to get you up to speed. I Switched to Michelins cross terrein's (38 pound tires at the size of 265-70-16's) for my normal driving and I now see about a 2 mpg gain on fuel economy. I can BARELY hear these tires as they have far less rolling resistance yet still they are rated for have great tracksion and I notice that my engine and trans does not work as hard to move the tires. These tire are pricy and cost me $760.00 not inluding a 60 rebate from costco.
Obviously, I'm working on having a off road set ready to rock when needed.
I am changing before catty o2 sensor this week and i'll see is that helps with fuel.

 

I'll be increasing my fuel economy by buying a late '90s Civic and having the Runner for camping and winter driving and I won't mind piling up miles on the Honda.

 

i try to maintain about 73 on cruise control and avg 20mpg, RPM's = ~2250.
ive gotten 23mpg when cruising for the full tank

my mileage didnt vary when my avg was 60, 65 or 70 by more than 1mpg

 

You have to take into account our locations. I'm at 4,500-5,000 above sea level, and have a much more hilly terrain. That probably has a lot to do with it.