Does anyone out there have more ideas for power and mpg's? My 04 SCrew 5.4L 4x4 is pretty much tweaked from what I can do with a limited budget. I'm running a hypertech tuner @87 octane, custom dual exhaust, S&B CAI. This thing has to have more power, pulls good, but like a slug on the hills with an 18 foot car hauling trailer with a car on it. 13 mpg's with a load. 14-16mpg's in town driving. 16-18 mpg's out on the hiway dry pulling no hills and driving @ 65 mph, mileage goes to the toilet above 65. I have considered underdrive pulleys and a jet performance Mass air flow sensor. Oh, and I tried that SLR "chip" bs too, that got sent back the same day, all it does is cuts out the mas to dump more fuel into the engine and engine check light. If any body has suggestions, It'll help.

 

what motor do you have?

what cab, drive train configuration? what mods do you have? what do you ue your truck for? etc

 

5.4L automatic 4x4 supercrew, S&B CAI, Dual exhaust, Hypertech. Everyday driving and occasional pulling loads on a trailer.

 

you're running a CAI and a canned tuner???? not a good combo, if I were you'd Id take that CAI off until I got a custom tuned tuner like an Xcal3, livewire, diablo or gryphon

 

X2, If you want to keep the S&B get a custom tune and sell the Hypertech. 04's run lean stock and get worse when you add a CAI.

 

But I think that MPG is pretty good from the sounds of the terrain and load.

 

DO NOT get the jet MAF, it's a waste of money




what size are your dual exhaust pipes? is it a true dual or a single in dual out muffler / cat back?????



what gears do you have and what size tires?

 

Thanks for the threads, I've considered all. I kept my hypertech programer because I bought if for my first SCrew, this is my second one. 2.5 in pipe for the exhaust, the pipe bender that I use doesn't go any bigger. I knew the 5.4L 3v ran lean, but I did not know the hypertech and the S&B would actually hurt my progress. and the gears are stock.

 

Ya, your probably running lean. Tuners are designed to work with OEM intakes, not after market. And after market CAI's are designed to work with the OEM PCM calibrations. If you want to run both, then you need custom tuning. As for a tuner, I like Bill's tunes from PHP, but there are many opinions on this forum. Do some research and you'll find what you like.

 

I have the gryphon and am waiting for the custom tunes to come in. I bought at the same time a K&N intake. It says right on my invoice from php that I can run the intake with the "canned" tunes while I'm waiting for the custom tunes as long as I'm running the level 2 setting. It seems to be fine.

 

Get the Xcal3 from VMP Tuning. Justin said that he's dyno tuned a lot of trucks and the S&B was one of the best flowing intakes as well.