I'm a newbie to this board and to Ford trucks, but I just wanted to know what things everyone has done to increase MPG. I have a '05 4x4 5.4 Screw w/ 285/65-18 BFG AT's on the stock wheels. No other mods save a straight exhaust that was achieved by replacing the muffler-back with a y-pipe and 3.5" tips coming out the corners. Truck has 72k on it.

My '99 Silverado I had before this truck with 285's on 16's would get about 14 in town and 17/18 highway. This F-150 seems stuck at about 10-11 in town and 14-15 highway. Whats the deal? The 285's aren't that much of a killer to the 5.4 are they? I can barely get 300 miles on a full tank before the dinger sounds and I have to go fill back up.

Also, went to the dealer I trust the most in the area and they quoted me $175 PLUS parts to change my plugs, does that sound right? I trust they know how to do it right, me and the tech talked about it after I talked to the counter rep.

 

I've got about the same setup. 5.4, 4x4 screw, 3.73 gears, same wheel/tire size. I get from 13 to 15 around town driving. Just took 14 hour highway trip and got a bit over 16 for the round trip.

I have a Magnaflow cat back exhaust, AirRaid intake and electric fans.

Driving style and habits probably have more to do with MPG than any of the mods either one of us have.

 

I also meant to mention that I drive like a grandpa. I am never in a hurry unless I am running late for work. I like to just cruise around

 

When was the last time you replaced your fuel filter? How about air filter?

 

Air filter only has about 3k on it...but the fuel filter will definitely be changed soon, those are the kind of ideas I am looking for!

 

You might have an excessive carbon buildup in the engine, especially if you drive like grandpa.

Go bring it to a highway and just floor it up to 65 mph a few times with a can or two of BG44k in the gas tank. It'll blast the carbon right on out of there.

 

Just got back from a 150 miles trip.Did 17.3mpg with winter fuel and stock tires.

5.4L flex fuel, fx4, 40 series flowmaster dump before the axle and edge evo level 2.

 

Car & Driver said they were getting 10-11 MPGs but they drive it like they stole it...

 

yeah that's fair for a plug change, unsure if you know, but there is an issue with breaking plugs off in the head.

i am getting over 400+ miles on a tank and i'm on 35's. temperature and winter gas don't help mileage at all. my last truck was a 00 Z71 on 285's and i was getting the same as you. how i miss that truck, i'm close to buying another one for my daily driver and keeping the screw for play.

 

Get a catback system and a custom tune.

 

I have a 08 and in town i get from 10-13 and on hwy i get from 17-21. I drove like 50 miles one way yesterday and was on cruse at 65 and was getting 21mpg, stock 275\65\18 tires and volant cai and flowmaster 50 series delta flow exasut. I was still getting these numbers in stock mode but my in town mpg came up and bit after. Do you guys have the digital message center? Mine does and when i get on the hwy i hit the reset button after i get on hwy and up to speed it recalibrates it. Not sure if you have message center but try that to see if your mpgs are any different.

 

Your truck is heavier than the 99 Silverado and was the Silverado running on the ethanol blend that you most likely are now? The ethanol accounts for about a 10% mpg loss.

 

The weight difference does make a big difference. Silverado's are usually a hair under 5,000lbs where as a common Supercab 4x4 6'5 bed is 5200lbs and a Supercrew 5'5 is around 5500lbs. I'm averaging 15 with mine, 14 city, 18.4 highway, 15 - 16 average because I dont live in a stop & go community. Those BFGs add to the weight too.

Changing out the fuel filter would help, my filter needed changed badly, my engine light came on because of it, and i noticed my truck was faintly weaker on the take offs because of it.

 

I usually get about 280 a tank. 10.8ish is my average I drive mostly short distance and im in and out of the throttle. I drove my avalanche the same way and got around 15+ mpg. I guess its just this type of motor likes da fuel. I honestly have just put the bad mpg out of my head because if I though about it too much id be getting rid of it.

 

On my registration paper, my truck is 2744kg/6050lbs.

Supercab fx4