How's your gas mileage?

[jtaborsky]

I just filled my tank yesterday and calculated around 10mpg. Vehicle is a 1987 Bronco II 4.0L 4wd with 4" lift, 32" mud tires, and 4.10 gears. All driving was 4wd and I let it warm up about five minutes before driving, which doesn't help. Still 10mpg seems really low.
Tell me about your vehicle, driving habits, and gas mileage.

 

[Vindictus]

2011 4.0 2wd manual
I get 18-20mpg about 95% of my driving is highway at 65 - 70 mph
I run 235/75/15 Copper something...

 

[Uncle Gump]

I know I spent a week in northern Michigan over Thanksgiving. Lots of two tracking in 4WD and also way more idle time then normal. Was right around 11mpg for that week. The trip there and back home was close to 17mpg.

This was with my 06 4.0L SOHC.

 

[Blmpkn]

'21 leveled 2.5" with 32" grabbers

I get a bit over 17 in the winter and 20-21 in the summer according to the truck. My speedo isn't corrected for the bigger tires though so the real numbers would be a bit higher.

 

[jtaborsky]

2011 4.0 2wd manual
I get 18-20mpg about 95% of my driving is highway at 65 - 70 mph
I run 235/75/15 Copper something...

I think your mpg sounds low. My 2010 Explorer 4wd 4.0 gets 22mpg doing 80mph, so I'm surprised yours isn't higher. Thanks for the reply.

 

[gaz]

@jtaborsky
A manual BII turning 32's with 4:10 is almost as good a match up as you could have. I would expect 100% better fuel economy, even from a much heavier Explorer with that setup.
-That is really low mileage even for putting around always in 4 wheel.
-warming up your engine will only improve your driving fuel economy. The engine performance is optimized when at normal operating temperature; everything works as it should once all the metals have heated and properly expanded, until then performance will suffer.
-when practical I recommend taking a look at your valve train: ie #1 the valve guides, possibly the valve seats and push rods/rockers if time and budget afford it. If your 4.0l has more than 35k miles on it the non-adjustable valve train's rockers and pushrods will have significant enough wear to adversely effect it's overall fuel economy.

 

[cyclejohn]

1984 Bronco II, 10K on a rebuilt engine, 4X4, base model, manual front locking hubs, Duraspark conversion, Holley 350CFM carb, mostly 2-lane country backroads, 3-speed auto, ...

23 - 25+ MPG with me driving. With my daughter driving, not so much .

 

[superj]

Stock 2wd edge on stock size tires with 3.0 and five speed stick. At 80 i get 19mpg and 17 in town

 

[4x4prepper]

Using a GPS to track miles, unless I was running P235s. My 2.9L autos about 18 mph, the 5 speeds up to 21. My current 2.8L 5 speed with mostly city driving or hauling a trailer, 12 mpg. I do get 15 mpg hauling a small 5x9 UHAUL trailer when empty on the highway. Add 1,000# and it goes down to 11 MPG. My current B2 is pretty beat up body wise, so, aerodynamic it is not and the ghetto 3" bodty lift does not help.

 

[rusty ol ranger]

87 Ranger 2wd 2.9/TK5/3.45 rear ~20mpg with an average foot at 90% 55-60mph cruising

 

[Elutheros]

It's bad! 5.0 pushing 33's with 3:73 gears. 13mpg cruising at 70 most of the time. I think the additional ethanol in the fuel is not helping. I'm constantly trying to tune is for better economy (running Megasquirt MSPNP2 ECU) but it just doesn't get any better.

 

[rusty ol ranger]

I just filled my tank yesterday and calculated around 10mpg. Vehicle is a 1987 Bronco II 4.0L 4wd with 4" lift, 32" mud tires, and 4.10 gears. All driving was 4wd and I let it warm up about five minutes before driving, which doesn't help. Still 10mpg seems really low.
Tell me about your vehicle, driving habits, and gas mileage.

I forgot to add, with bigger tires if you didnt change the speedo gear your speedo (and odo) will be off. Youre actually traveling further then what its reading. That could be why you think youre getting 11.

My 460 gets 11 in an F250 with 4.10's. If its running good id bet on the speedo.

 

[Eddo Rogue]

Vehicle: Beater
Diving habits: Vehicle is a stolen rental and everyone on the road is trying to kill me.
Gas mileage: Not much.

 

[cbxer55]

1998 3.0 automatic, street truck on 15 inch rims. Mine is doing over 20 mpg as of late. Last year had some running and starting difficulties. The EVAP hoses ended up being the culprit. Deleted that crap. The EGR valve is stuck in the open position (assume broken spring), deleted that crap. Catalyst doesn't appear to work, can tell by the smell. Runs awesome, starts first turn of the key, gets over 20 mpg. The last few years, I was lucky to get 15. I drive it like I stole it most of the time. Ford says to prevent carbon deposits, drive aggressively. I do!

Even odder, the last 15 years or so, the truck has pinged, badly on 87 octane. Even mildly on 91. Was running 93 most of the time. After doing the above, I am now able to run 87 octane, and no ping. Amazing!

Forgot to add, my truck has 4.10 gears.

 

[jtaborsky]

I forgot to add, with bigger tires if you didnt change the speedo gear your speedo (and odo) will be off. Youre actually traveling further then what its reading. That could be why you think youre getting 11.

My 460 gets 11 in an F250 with 4.10's. If its running good id bet on the speedo.

My 460 also gets around 11 in my '93 with 4.10's. I've converted to mass air, added a quarterhorse (RIP), and been working on the tuning to improve it.

I did the math and concluded the original combo (205 tires and 3.45 gears) is roughly equivalent to the current combo (32" tires and 4.10 gears). I didn't mention that my transmission is rapidly eating itself. I excluded that to determine how much impact that factor had on my mileage without receiving unwarranted speculation. At one point I was getting 20mpg.