hi everybody,thank you for accepting me.
heres alittle history on me, and most of this needs to be probably posted elsewhere but not shure where and im a newbie on fourum sites anyways.
i bought my very first ford truck around 2012. 2008 one ton, single axle king ranch. bought with 50,000 miles.bought a extended warrenty because heard deisels very expensive to fix,work on'.less in a yrs time the truck was in shop more than i drove it,had more miles on my boots than truck. i LOVED insie,inside room,truck bed room,but under the hood nothing but trouble.needless to say i traded it in,lost 20 grand due to being downpayment and being completly upside down.ji traded in for a used 2008 dodge mega cab.and swore never again on a ford,[been chevy fan for life].trucks 6.7 motor has been awesome,but everything else p.o.s.
so ive got severe back issues now and tired of fixing vechicles.
im on limited income now, So i sold alittle piece of property to i could get something newer.
i went to alb,nm to test drive a 2008 -450-ford lariet with 110,384 miles,6.4 motor
i bought it for 31,000. DROVE great on test drive.
so i leave car lot with truck and a 500 mile or 15 warranty. if truck had problems in time frame,return to dealer to fix.
it was a 344 mile trip home. next day realized front wheel drive shaft ball socket knuckle completly shot. 4wheel light indicator doesnt illumanate while in 4 low.(light does come on briefly during initial turning on key) i had to drive 125 miles to another town to help out on a job, i live at 7500 ft elavation.traveling to 3600 ft.
when i left out early morning, warmed up the truck, i just reached in turned key, to start so didnt notice dash symbols.
when walking back to house, heard motor rpms speed up, and truck got alot louder. i assumed cpu just sped up to warm up(even though wasnt cold,52 degrees temp)
loaded up and took off i noticed a big two opened wrench symbol by to odometer reading.
got to payment highway ,traveling to 9500 ft of elevation before desending to my destination of 3600. i pulled over after 5 min of driving, it didnt have to power id had when bought it,was vibrating,shaking,thought check tires and trailer i was pulling empty. i didnt have flat ,so i continued.truck ran bad,took 20 min longer to get up the hill than normal. i pulled over at pull over spot,popped hood and damn, was loud,clanky noise seemed to come form top of motor.
i turned off key,let truck set for 5 minutes.restarted truck, it returned to a quiet running deisel as before.power returned to normal,wrench symbol dissapeared, . 15 minutes of driving ,messaged popped up oftellimg me to continue to drive,CLEANING EXHAUST FILTER. i guess similiar to my cummins regenerating, before i did a egr delete,tuner
an hr later,it did the cleaning again.
truck is litterly getting 7-8 miles per gallon hauling empty or full.when coming home a week later,coming from 9800 ft elavation,down to 7500 (home) it starterd running like **** again,motor wsa racing,but seemed like i had no power.i watched rpms,stayed around 3500, but no get up and go.
WHAT IS GOING ON? dont have wrench symbol on, but im not happy with performane,power,and fuel milage.PLEASE HELP!!!!!

 

There is a barometric sensor that is supposed to alter engine specs based on altitude. Pretty sure key has to be turned off to allow reset to new pressure when started.

Try this and let us know if it makes any difference, thanks.

 

thank you hanky. i would of replied esarlier if id gotten the reply, like i said previously just learning on fourums.
im not shure if it reset or not,been parked since we got a ****load of rain dont want to be stuck.
but whats wierd when it first doing this,it was parked at my property at 7500 ft elavation,so obviously key was off when i started it,im headed back tommorrow to the town of 3600 ft elavation we will see how it performs.
on another note, whats up with the fuel milage? i know its a 450 but not pulling a damn thing it got between 7.2-7.8 miles to gallon.remember i mentioned it has the 6.4 deisel engine.what is your opinion on this truck? i feel i screwed myself

 

The 6.0 and 6.4 did have some problems. Folks that have brought them up to date with various revisions seemed to be happy with the results.

There must be other shops in that area that have had to deal with altitude problems and solved them. Have you considered checking out some of them?