'03 4.0 Mileage

[Curtludwig]

I see a few posts about making more power but how about making more economy? My '03 gets a rock solid 17mpg, worst tank yet was 16.9, best was 17.4...
My '96 Dakota V8 got 18 highway... So the average is better on the Ranger but the highway mileage SUCKS. What the hell, I went to a smaller truck to get better mileage.

Anyway has anybody ever tried a chip on economy mode? This thing has plenty of power for me, I'd be willing to give up some power for better highway mileage.

 

[Yellowsplash]

Is most of your driving done on the highway with speeds >55mph? What size tires and gears do you currently have?

 

[Twizzler09]

My '96 2WD 4.0L with 3.08 gears just got 22mpg on a 350 mile trip. About as good as it gets.

17mpg for mixed city/highway seems to be pretty normal for the 4.0 (assuming thats your driving habit)

If thats pure highway, have you ever done a tuneup? General maint stuff is the place to start.

 

[Curtludwig]

Its a bone stock 4.0l '03, I forget the tire size and need to check the gears. Last Saturday I did an all highway run and forced myself to keep down to 65mph, it looks like I pulled about 18mpg. Considering ~40 miles of that was loaded down with firewood I guess that was okay.
I've seen speed cause big mileage drops on other vehicles and my Ranger seems to be no exception. I think my problem is that the truck sits higher than I'm used to so I drive faster...

I've also taken the tires up to ~36psi which may have helped some.

What do you do for a tune up, new plugs and wires? Oh airfilter too I didn't think of that. After only ~28,000 miles I shouldn't think the plugs and wires are bad but of course its 6 years. Its a distributorless ignition I think so no cap and rotor.

I've never worked on an engine this new before...

 

[Big Jim M]

If you want GREAT milage drive 55 and no faster.. As for the tune...if it runs fine leave it alone. The vehicle will TELL you when it needs attention.
Big JIm

 

[badbronc92]

I've got an 03 4.0l and for a while I was averaging 20-21 on a mostly highway tank. We took a trip up to the mountains one weekend and on about 300miles I averaged 22mpg. I have 4.10 gears. Accelerate slow coast whenever possible and look way up ahead to anticipate changes in traffic to lessen the stop n go driving. Basically if you want good gas mileage drive with that in mind all the time. I'm in the process of averaging out my gas mileage with my 33s.