better mileage @ higher speeds

[zaffo oxnard]

I do't get this truck. I baby it (to the point that it annoys my wife) and I get at best 14 MPG around town. I drove it LA to Phoenix this weekend doing 80 to 85 mph the whole way and got 18.5 mpg even with 500 lbs of furniture in the back on the way home. In a truck shaped like a brick, this does not appear to add up. Over 50 mph my mileage should go way down because of the wind drag. Is the gearing of the rear end and transmission way off? I feel that I am often too heavy on the throttle at 40 - 60 mph just to get the thing moving. Do I need to keep the o/d off an let the 4.0L SOCH engine run? Can these engines do better under light throttle/high rpm settings rather than lots of gas / low rpms? It sure seems like this engine likes to run up at 3700+ rpms rather than at 2800/2900.



What gives? My 69 mustang with a clapped-out 302 got the same mileage.



zaffo

 

[Pat Freeman]

I feel the same way, Tony. Maybe there is a setting in the PCM to cut back on spark and fuel based on speed, throttle position and gear.

 

[Devin Underberg]

I was kinda wondering the same thing cause I seem to get better mileage doing 85 than I do at 65. I know its breaking the law but the spped limits here are 75 and 85 seems to get better. Maybe there is something!

 

[Rodger Tellefson]

You forgot to figure in the power to weight ratio, and with all that starting & stopping in town is a strain on the engine. When you are crusing on the hwy. with the O/D on you are using very little gas to maintain your speed at lower rpm which gives you better gas milage. What gear ratio is your differential? You won't get as good a mpg as the 3:73. You will accelerate better with the 4:10 ratio, but mpg will go down. Check our profile to mods that will increase you better mpg numbers. I would start with changing to a good synthetic oil, then a CAI. The best bang for the buck has been the SCT XCalibrator 2 tuner with the 87 mpg tune.

 

[Jeff C]

Devin, of course, the speed limits are set by the government, so it's GW's fault; and since he happens to have oil ties and is in charge, it's all a big conspiracy!

 

[Richard L]

I have had two Sport Tracs and have driven each from Texas to Ohio on several trips.



I drive a very consistant 70-75 MPH with an occasional burst up to 80 MPH. I have always gotten about 20 MPG with a minimum of 19.5 MPG. I have gotten as good as 22.3 MPG. All that with about 500 lbs in the bed.



I found that driving at night between about 12:00 Midnight and 06:00 AM you can get the best mileage since there is nobody on the road. When I drove to Louisville, KY this past June, I left at Midnight and drove throught the Dallas area and nearly to Tyler, I don't think I ever had to touch the brake pedal until I stopped for gas.



I think the slowing down and speeding up, even just 5 or 10 MPH because of heavy or slow moving traffic really cuts into your gas mileage. Once you get that momentum going and don't have to slow down, the mileage makes a noticable jump.



I have always said that, if you live around larger cities or in the Northeastern US, the vehicle density will cut your mileage simply because even on freeways, the congestion will constantly require you to speed up and slow down and that eats up your gas mileage.



...Rich

 

[Thomas Rogers]

My '04 recently got just over 20mpg on a recent highway day trip (440 miles, most all highway), and I only get 15mpg regularly around-town. When on that long highway trip I was traveling at a speed of around 72mph.



TJR

 

[Aaron Yarbough]

I have noticed that my best fuel economy comes at about 73-75MPH.



Also, it seems that the cruise control optimizes fuel economy more than you can do it by manually maintaining a set speed yourself. I think the cruise control not only controls engine acceleration but I think it also modulates the auto tranny in some way which adds in fuel economy as well. I use my cruise control all the time, even to overtake cars on th freeway and then decelerate back to my cruising speed.

 

[Gypsy me]

Yep that cruise control is a good thing. If you don't use it then, od off when climbing or wanting to slow the engine down works for me in my 04

 

[Larry Phillips]

I didn't get too good mileage @ 120. :lol:



My parents have pulled much better gas mileage at 65 then I've been able to do at 70.

 

[Gypsy me]

Larry...release the lead foot!:lol::lol::lol:

 

[kil roy]

Devin, of course, the speed limits are set by the government, so it's GW's fault; and since he happens to have oil ties and is in charge, it's all a big conspiracy!

198.8 RWHP 1st Gen '01 Job2

:lol::lol::lol: