Although 24mpg is still on the high side IMO, it is a more realistic number than 27.



You got it!

 

Must be cause i'm still reading it

 

I never guessed I would get a full physics lesson here. Though it kind of seems appropriate now that I think of it. Any thoughts on relativity or existentialism?
Sorry for the smart a$$ comment. Sort of.

 

Ok,my bad considering the all hwy driving but city driving mileage is directly associated with the extra weight being a hinderance when it comes to stop and go traffic plus with AWD it's still powering all 4 wheels all the time as opposed to a 4wd system that is inactive at the time of driving.

 

Learning something knew aint never hurt anyone

Here's another interesting tid bit: it takes exactly 1hp to lift 550lb a distance of 1 foot.

So traveling in a 4400lb vehicle up a 6% grade road at 65mph for 1 hour would lift you 20600 feet and would require an extra 46 horsepower versus traveling on a flat road. That's in addition to more than 50 horsepower it takes to overcome air drag in an SUV.

That's almost twice the power, so 20MPG / 2 = 10MPG is very realistic figure. It's all very exact, there is no magic when it comes to MPG. ;-)

 

haha this is an interesting thread now. but ya i'll run a few more tanks in the same situation (highway)

but ya, i think i may have jumped the gun on saying 27 but whynot!? i got stoked i calculated that then ran the full tank & got 24mpg, regardless tho, my intent was to just thank all the information i read about on here that got me that kind of mpg (20+) b4 this i only got 18mpg on the freeway so getting at least 24 than 18 is a deal to me. but its all good

 

The best I got was 23.3 in my '01 Taco Prerunner w/ the 3rz, coming back from Jacob Lake, AZ to Phoenix. Average speed 75ish but it's all downhill. I suspect though that the Taco has worse fuel economy on the highway than the 4Runner, on account of having suction behind the cab and tailgate rather than just the gate.

 

Didn't Mythbuster's squash that myth ?

 

the bed doesn't affect mileage that much. tailgate up is the way to
do it.

tailgate removed with a net...they found the best results overall. but
the percentage diff is so tiny as to be moot

 

How is 24MPG "about right" when you've got a 2WD 4-cyl. engine and he's got a 6-cyl 4WD? And you couldn't even get 24MPG.

My 4Runner and Tacoma (both 3.4L 4wd) have all gotten the exact same MPG.

 

I could see the the Tacoma and Runners being the same. The Tacoma has the issue with draft and such in the bed, but is lighter. The 4Runner may have a slight aerodynamic advantge but is heavier.

 

With the breathing mods he's talking about and rolling on pretty much flat territory, it seems reasonable, much more so than 27+. There are a few guys over at CustomTacos that reported the same thing. The thing that killed it for me I believe is the climb back into Flagstaff from the res; with the 4-popper I had to shift down to maintain 65-70.

 

Breathing mods?? Please give me one solid evidence that these "breathing mods" do anything for MPG's. I've tried most of them. Waste of money. And again, you have a 4-banger 2WD. He's got a 6-cyl. Your MPG figures are irrelevant.

 

I don't think that is the case here. I agree aerodynamics affect MPG figures, but not at the rear section of the vehicle. My Tacoma had a shell till about a year ago. I took it off this summer and left it off. The MPG figures were exactly the same. And that MPG figure is the same as my 4Runner I had before (21MPG 80-90% highway). All of these vehicles were stock with 265/70/16 tires.

I think at such a lower speed (which is about 70MPH for me), rear aero really has little to no effect. Weight doesn't have that much of an effect, either, as my Tacoma DC is about the same as a 4Runner in weight.

Note that I commute about 80 miles per day over the same terrain (highway), so the test grounds are consistent. Also the data that has been gathered for these vehicles are at least a year long or longer, ruling out climate changes.

 

I thinks it going be really ahrd for anyone to compare mileage. My commute to work is all city right now and speeds never go above 50 mph and is all stop and go with idling at stop lights. I used to live 8 miles further from work but it was mostly highway. I drove further but got more miles per tank due to increased mpg. Everyone's driving style is going to be differnt, different terrain, and enviornments etc.

 

Good to know that when i swap out my 25MPG 3.0L that i can get my 3.4L up to at least 27MPG. What is your PSI in your tires?

 

Go check out CustomTacos, and look for Gadgets dyno data; it's there in black and white. As for having the 4-popper, the disappointing truth is that the mileage figures are very similar; no real gain from running the 3rz, both in my experience and that of others on the forum.

 

Yes,breathing mods will have a slight bump in a little wheel horsepower but cacklak meant MPGs and I've tried opening up things and haven't really seen any consistent gains either.

 

Power improvements result from increased efficiency though, other things being equal. The problem I think a lot of guys run into when they get a little more out of their ride is that they play with it, consciously or not, and that negates their gains.

 

Ahhh, this thread brings back memories...