Does anyone know what I can do to get better gas mileage on my 04 triton 5.4

 

Drive like you have a raw egg between your foot and the accelerator and keep the rpm below 2K. Keep the speeds at 60mph or below. It's a 6K-pound truck with a 300HP V8 and a 4-spd transmission, it's not going to get 20mpg unless you drive long stretches of highway at 60mph max.

 

I never did better than 15.5 mpg on Interstates (75 mph) when I had one.

- Jack

 

With the 3.55LS rear end, I can get 18mpg if I am all hwy and keep it under 65mph. Anything above 65mph really starts to drink fuel. At 65mph my rpm sits right at 1,800rpm. I rarely drive that slow though. I can get about a 1mpg bump if I use zero ethanol fuel, but it costs about .30/.35 more per gallon, so it's a wash in terms of cost/mile vs E10.

 

75 will kill mileage for sure.

I can run steady at about 65, anticipate grades, go easy on throttle, and see 20 or even 20.5 on I-81. Speed limit is 70 or 65 or 60 depending on location. I try to limit my speed to 65. I figure if I just stay right, let others pass, I'm still making better time than if I were over on rt 11 running 55 and slowing in towns, plus Rt 11 has more curves, so longer distance.

Then there are those times I just say screw them on 81, and I stick to 11 and run 55 max.

But if I chase the 70 mph limit, make passes, get in the line, yeah …. 15-16 is about right.

3.55s and OEM type rubber, 275/55-20.

 

Pump up the tires to 40psig if they are rated for 44 max. A tuner program might help a little. Run p-metric tires in the stock size. Don't raise the truck.

 

I just cleaned the throttle body, MAF sensor, fixed the failing foam around the air filter that was allowing unmetered air in, and went through all the coils to make sure the contact was as good as I could make it. I did the relearn procedure via Makuloco on youtube. Before doing all this my mileage touches 17 on a fresh oil change while driving 70 to 72 or 73 on interstate highway. Drops to 15 16 after a couple tanks on the oil change. This was going out of state to work for a period of time, which the truck stayed parked once I got to the work location. But now I am home and going to be doing local country road driving of 60 61 62 max and really see if I can break 18. This is a reman engine with 34k on it and it runs quiet and strong save for the noisy fuel injectors that make one hell of a racket. The factory engine back 14 years ago scraped 19 driving lower speed local country roads and consistently got 16 17 on interstates.

Will update when I see, may take several weeks to go through this tank of non ethanol fuel I put in. All the figures I referenced above were on 10% ethanol fuel.

These figures I am fixing to get will be on no AC as well, so a summer figure will be less.