Got a ? here...My truck which is a 6.4L F250 was in the shop prob a month ago maybe a lil less, but anyway the boost while crusing down the highway at 70-75 is at like 22psi and sometime rarely hitting 12psi...but b4 i took it in to the shop it was at 12psi. when crusing the same speeds on flat ground?? why has it changed and sometimes goes back to what is used to run at?? and isnt this hurtin my gas miliage? i asked the dealer and they told me if something was wrong it would throw a code..so now what happens if i hook to a trailer w/ a 7000lb truck on it and tow it at 70-75 is the boot gonna be at 32-40psi?? just wondering

 

Need more if on your driving conditions, my truck will run about 12+ psi if its flat ground and no head wind at all. A little head wind and im around 15+psi easy. Gearing would play a factor as well. As far as pulling, when i pull my 12,000 trailer im 25+psi the whole time unless its down hill.

 

i got 3.73 rear end and this is normal flat ground driving w/o pullin just back and forth to work same route same days...and ya i know with head wind you get higher psi but these are normal 5-10mph wind days...im just sayin it hardly ever got above 20 unless i was goin uphill or gunnin it, until they messed with it.

 

Under moderate accel, i'm over 20 ever time i take off from a light.

 

What job build is your truck 1,2,3?

 

ya that too sorry to mention taht im talkin about cruising though...

 

its a job 1

 

My best guess would be that you might have gotton the most recent updated reflash which changes the shfit stratigy which might have a slight affect on the engine perfromance. Just guessing IDK.

 

ya i noticed it seems to shift for me better...and they said they did reprogram it...i was just tryin to figure out if this was normal and u think its hurtin my gas miliage more...cuz seems like im fillin up more but the lie-o-meter seems to be runnin normal.

 

Well its a toss on that one, some people claim a decrease in milage and some claim it got a little better. These trucks are very touchy and milage is adversley affected by how each diffrent driver drives. Very diffrent from the old 6.0's. Best way to figure the diffrence in milage is to compare a hand cal fuel from the truck prior to the change to a current hand cal.

 

ya...im noticin that aswell...thanks for the help