Thanks for your post! I have two F150's and I am in the MPG hunt.

Sorry, I don't tow much, and I don't do burnouts anymore, but I damn sure need to pass on 2 lane highways. I think 2000 to 2200 rpm is a good place to cruise.

The 05 5.4L has 122K miles on it. Lifetime average of 15.3. Put Michelin highway tires on it, stock size 265/75/R18, and it took me to 15.8. mpg. Really. I ran 105K miles on 2 sets of stock tires before that change. Next, I installed the Troyer electric fans and the underdrive pulleys at the same time, and the gator back belt. That took the truck to a solid 16.8 mpg average. (I have seen a low of 16.7 to a high of 17.1) OK, so the next thing I did was the Gotts CAI mod. Damn, looks like it is taking my mpg down or no improvement. But the pedal seems so touchy now. Lots of pep, but no mpg improvement. So, I have just ordered a gryphon with NO custom tunes hoping I get some benefit from the CAI. I intend to go to HHO and perhaps an exhaust system change? Anyone care to tell me what to do next? What brand(s)?

I will wait for all my mods before I get custom tunes, unless I hear otherwise from y'all.

The 06 5.4L has 52K miles on it. Lifetime average of 15.3. Put an Amsoil air filter element in it a 18K miles and it took me to 15.7 mpg average. OK, but maybe I just needed a new air filter? I also changed out the trans fluid with the Amsoil synthetic but I did that just to keep the truck for 300K miles. I put Wrangler tires (265/75/R18) on at 50K miles, and they took my average mpg down to a solid 15.0 mpg! dammit. Made the Gotts mod CAI just two days ago, and it took me down to 14.3 mpg! Arghh. No tuner ordered for this truck yet, but I want to see what the first gryphon does.

What mods do I need to improve mpg? In what order?
Is it time to change the plugs in the F150 with 122K miles? What kind of plugs?

What custom tunes are the best on the gryphon?

Please be kind, I am an old fart, and a computer nerd.