I can't complain on the fuel mileage of my truck. I've got a 99' F150 extended cab flareside sport. 4.2 L auto with 3.55's. I"ve got the 255/70/16 tires on it as well from factory. Only thing I've done to this truck is put on a flowmaster si/so muffler with 2.5" pipe with a 3" tip. (basically cat back system) and K&N filter. ON average, 600-700 KM per tank(18-21 MPG) is not uncommon; year round. Winter driving usually nets closer to the 600 Km range, but during spring/summer months, 700 KM is quite normal. I drive around 65-70 MPH all the time. Combined city/highway driving is usually around 18 MPG. (this is with the majority of the driving happening around the city)

I have invested in a MAC intake to help out with the breathing and hope to pick up an additional 1-2 MPG, but we'll see what happens when I get in on in the next few weeks.

One thing is for sure, I'd be looking for a different vehicle if I couldn't get at least 18-20. Anything less is unacceptable. If I would get less than 18 MPG, I may as well be driving a 5.4L!

 

Caddman, how many miles did you have on your truck when you got the O2 sensors replaced?

Also, does anyone know if fuel injector cleaner makes a big difference in gas mileage? I have about 53,000 miles on my truck and never used any.

 

You Honestly can not tell me, you expected no issues on a used domestic vehicle. There is no way to tell if the previous owner took care of it.

With that said, my old 97' had the same problems (it was my first ford truck).
Replaced in order.

Spark Plugs and wires
Cleaned and honed the intake ($75 bucks at the machine shop)
Replaced seal on intake and headers
Replaced headers
Entire exhaust re-done
New Fuel Injectors (worked great for two months)
O2 sensors

In the end I learned one thing when I met the previous owner that made me immediately have an idea.
"I don't know, I just put the ol regulaarrr in there and she runs pretty good".

Went to premium and one injector cleaning later, I went from 13 mpg to 19 mpg city and 18 hwy to 21 hwy. Try that. Besides your truck will love you for it.

 

Yes and no:

I've been using FI cleaner with my truck at every other oil change (4 bucks a bottle isn't that bad) on this vehicle since new. My old 97' had to be professionally cleaned because they were fouled too bad and he told me a nice little piece of advice. Too much of a good thing is still that, too much. He went on to say that while most of them do work at getting the spray even again, when people see a difference they go overboard and continually use it which somehow wears out almost everything in the injectors with overuse. I'm at 85,000 miles doing the cleaner every six months and I haven't had a problem yet (knock on wood). But maybe I found a good middle area to do this in.

 

Im sure the 1/4 ton of steel in the back for winter weight doesnt help the mileage.

 

Ohh I understand about the FI cleaner. Maybe I'll just try it once and then let it be. Thanks texas_fordlover

 

I agree. We have 3 Fords and they all were bought new. We have a 1999 F150, 1999 Windstar, and 2000 E150. We too have a long list of problems. Windstar had a tranny replaced too @ 80k miles. My F150 has problems with Tranny. I have replaced the ABS sensor, Voltage Regulator, and fixed the Door Crack. The E150 also has had some tranny problems. Build quality is lacking in it also, but I attribute it to the aftermarket builder.

Lets just say at 5-6 years old I do not expect these cars to be falling apart. Like all have tranny problems. I have had car before last until 200k on original tranny. I got this in my Japanese and German cars. I agree with you that Ford will not be getting anymore of my family's business.

 

I just filled my truck up for the second time since purchasing it a few weeks ago. I did mostly city driving and a few short trips on the highway. I was very disappointed with the mpg's. I averaged 14.3. I have a 5speed, 255/70 -16's, and not sure about the gear ratio. I put in new plugs today and a new air filter last week. I was leaning toward a 4 cylinder ranger, but everyone thought I should get a fullsize since I'm pretty tall. The F150 is very roomy, but I'm paying for it at the pump. I hope I can get around 20 on nothing but highway trips, but that may be wishful thinking.
Joe

 

I had a 2000 F-150 Scab 2wd XLT, 4.2L, auto, 3.55 rear end that I leased new. While I had it, it averaged 11-12 mpg no matter how it was driven. I got rid of that and leased a 2002 Scab 2wd Lariat, auto, 4.6L, 3.55. Got 11-12 mpg out of that one too. Lease ended, turned it in and purchased a 2002 Screw 2wd Lariat, 5.4L auto, 3.55. I have only had this truck 3 weeks now and have yet to do a mileage check, but I think it might be close to the other two.

Since I have now had all 3 engines, my opinions on them are:

4.2L V-6:
Good engine, needs more torque at low rpm, decent at highway speeds, has to work too hard in these trucks which contributes to lower mileage than what you would think for a V-6.

4.6L:
Strong engine, has plenty of power for moving the truck as you want it to, does a decent job for occasional light towing and hauling. If you don't do any towing and you're not a speed demon, this engine will serve nicely. It's pretty much bulletproof.

5.4L:
Strong engine, great torque at lower rpm, good choice for towing and hauling, excellent potential for mods.

Bottom line is, whatever your needs are, one of these engines will fit the bill. Remember, these trucks are not in the same weight class as a Ranger with a V-6. The power to weight ratio for an F-150 with a V-6 is completely different. The harder the engine has to work, the less mileage it will get no matter how many cylinders it has.

 

I leased a new 01 just like yours and drove it to 24k, that is better than I got. In fact, I would say more like 14-15.5.

My 5.4 4X4 3.55 is running about the same. 350 miles was the most I ever got out of a tank on a trip, and that was in the 5.4, but I never really took the 4.2 on any long trips where you run the whole tank out in one day.

There was nothing you could do to drop the 4.2 below that 13-14 area though, and i've had the 5.4 4x4 down to 10.

 

I'm getting 15 mpg in my 2004 Heritage F150. that with a 4.2 V-6, 4X4, and a 3.55 rear , my tire size is 255/70/16 that factory size.

 

For more room and a bigger truck, a F-150 is better then a Ranger, and they don't get the mpg, I know a guy who has one with 4X4 V-6 and he gets what a F-150 gets for mpg.

 

So, not to be ****y, but why bother posting in a Ford F150 Forum if you're so unimpressed?

 

I get about 550-600km per tank....not sure what that is in miles though...

 

I've increased my gas mileage by purchasing a ScanGuage. I stare at the dam thing constantly and now tend to be light-footed being able to watch my MPG instantly. Just got a tonneau. Will be interesting to see if Hwy mileage improves. The consensis is 1-1.5 mpg increase.