I have a 2005 Lifted F150 with the 5.4L and 3.55 Gears. When I am climbing elevation on the freeway I constantly lose power and have to really press on the gas to maintain speed. It shifts back and forth between gears way too often. There is a sweet spot that is hard to find and maintain. I waste a lot of gas as a result of this. I know the tires and lift add a considerable amount of weight but there has to be a way to fix this. I also use a Superchips Flashpaq but haven't tried many settings. Any suggestions?

 

Take the overdrive off until the top of the grade, that way the trans doesn't hunt for gears and you can use less of the gas pedal.

 

I am not sure about the Superchips but is there a setting on it to adjust your tire size?? That would help a bunch...also the 3.55's arent the best at keeping it in the sweet spot when the truck is stock much less lifted!!

 

Yeah I have the programmer set up to match my tire size, gear ratio and octane set at 87. I also have the rev limiter adjusted. It has numerous settings for shift point and shift firmness and so on. I have all settings set to Superchips value. I can try different settings but instead of trial and error I figured I could just ask someone who has already done that.

 

I have thought about a gear change but I believe that would make my mileage worse using smaller gear ratio. I am currently getting 15-17 mpg because I mostly drive freeway. I am afraid of losing MPG and changing gears will really dent my pocket book.

 

I drive mostly freeway and my truck is stock and I get 15-16 average....granted I am running 70-80 most of the way...
If you are getting that good of mileage that rocks!!

 

regear it. 4:10 or 4:56 will help alot.

 

With larger tires a gearing change (within reason) will usually help your mileage, especially city mileage. 3.73 at minimum though this will only increase torque output per tire RPM by about 5%. 4:10 will help, about a 14% increase in torque output per tire RPM.

No way around some things, if the PCM determines there isn't enough torque to maintain driver demand its going to down-shift. While you can play around with settings to move shift points around, the Flashpaq isn't going to give the level of control really needed to get this right, custom tuning is the answer (and you'll get more power as well which will help). With custom tuning the shift maps can be finely tweaked by the person writing the tune across the entire RPM range instead of just absolute values like the Flashpaq gives.

 

Lock OD out, and select a speed the engine will pull in 3rd gear.

Or, a supercharger......