Bad Gas Mileage

[idaboogeyman]

I have a 91 f 150 extended cab 4x4 with a 5.8 in it and gets the worst gas mileage you can immagine can anyone give me some tips on how to fix this problem? THANKS

 

[Brian_B]

What transmission do you have?

My dads 88 F-150 4X4 gets horrible mileage. It just has a 3 speed auto (C6) though. Nothing will improve it very much.

A good tune up, oil, filters, plugs, wires, and proper air in the tires will help some, but not drastically.

Welcome to the site.

 

[idaboogeyman]

Dont Know Much Bout Trannys But It Is A 4 Speed Auto In It

 

[Brian_B]

Then it should be an OD. That should help.

How is it running? Start well? Do you have a lift and larger tires? When was the last tune up?

What mileage is it actually getting? Thats the important one.

Just asking general questions.

 

[Skandocious]

Welcome to FTF Boogeyman.

What kind of mileage are you getting?

Brian's right about the tune-up, that can do wonders for gas mileage if you haven't done a tune-up in a while. Unfortunately bad gas mileage can come from a wide variety of areas. More details? How is the engine running? Any other things not quite right?

 

[O'Rattlecan]

I would also check for even tire wear. If the alignment is wrong or certain suspension parts are worn, you'll have a lot of drag.

Ryan

 

[blacksnapon]

General checks are in order. Making sure there are no fuel leaks, of course general maintenance items (air filter, tire inflation, proper ignition timing,etc). The 5.8 never was known for exceptional mileage to begin with.

 

[Skandocious]

I get about 12-13 mpg (highway with mixed city driving) with my 33" tires and 4.10 gears, and I consider my 351 to be pretty healthy.

 

[Brian_B]

Yeah..sounds about right. Dads 88 gets 10 on the highway (on a good day). His is the 351 (5.8 liter for those of you who use coke bottles) and the C6 though.

They say his new to him 97 (4X4, 5.4 V8) will get around 20 on the highway. He had not driven it enough yet to tell.

 

[Skandocious]

I've heard those modular V8s get pretty crappy gas mileage... Although I don't think it would be any worse than these oldies like mine. I'd be interested to hear what kind of mileage he's getting, keep us posted Brian.

 

[Brian_B]

Might be a while...he just drives to work and back (3 miles each way).

My boss has a 99 RWD with the 5.8 that gets 22 on the highway. I know..I have driven it on trips and checked it.

 

[O'Rattlecan]

before I got my new tires I regularly got 18ish.

Ryan

 

[Skandocious]

They didn't put the 5.8 in these trucks in 99.... Perhaps you mean the 5.4?

 

[Andyman8282]

I've heard those modular V8s get pretty crappy gas mileage... Although I don't think it would be any worse than these oldies like mine. I'd be interested to hear what kind of mileage he's getting, keep us posted Brian.

I'm getting about 22-23 MPG with full A/C on in the summertime, and the foot usually quite a ways in the pedal on my Modular 281 (4.6 V8)

Granted the engine is in a Thunderbird instead of a truck Little bit of a weight difference.

 

[Skandocious]

Hahaha yeah that weight might make a LITTLE bit of a difference

 

[Andyman8282]

I personally won't buy a vehicle that doesn't weigh atleast 3,500 lbs, it's just not worth it if ya get in an accident

Hopefully by the time I can afford a new car, someone will make a vehicle that weighs 3,500 lbs has 200 hp+ AND gets 40mph

 

[Skandocious]

I personally won't buy a vehicle that doesn't weigh atleast 3,500 lbs, it's just not worth it if ya get in an accident

Hopefully by the time I can afford a new car, someone will make a vehicle that weighs 3,500 lbs has 200 hp+ AND gets 40mph

Keep dreaming.

 

[Blue Goose]

I personally won't buy a vehicle that doesn't weigh atleast 3,500 lbs, it's just not worth it if ya get in an accident

Hopefully by the time I can afford a new car, someone will make a vehicle that weighs 3,500 lbs has 200 hp+ AND gets 40mph

I assume you meant MPG.....

 

[Andyman8282]

I assume you meant MPG.....

Right, my mistake Never realized how close the "g" and "h" were on the keyboard

 

[2speed]

I have an '03, with the 5.8, when towing my boat it gets around 8 mpg.
(boat weights around 2000lbs) but it has a high speed rear end in it. It would do better if i lived in Kansas or someplace where it was flat ground everyplace that i went.