An SCT X4 with a good set of custom calibrations from MPT will fix that.

MGD

 

Ah, good point. I didn't think of that.

 

Just picked up a stock 2010 5.4 with 80,000 miles. I was having the same issue I thought someone maybe left a tv in the bed lol. I took it to ford and they reset the transmission. I can barely feel it shift now it drives like brand new.

 

I have a 2010 f150 and it does the exact same thing except my nrake light doesnt come on. So maybe 2 or 3 times it downshifted into first hard. After owning the truck for 2 years. It's got 120k miles on it. I changed the tranny fluid and filter and now it downahifts into first hard everysingle time. I took it to a tranny shop and the guy put in solenoids and valve body from a core he had now the truck barley made it home it put itself in limp mode. He told me 1200 to rebuild it but after reading this thread i think i should put the original valve body and solenoids back in then take it to ford and have them reflash or reprogram the tcm. I really meed help on this one any questions please ask me. If anyone needs more details just ask. I dont have 1200 bucks laying around for a rebuild so if i can get some more info from yoy guys on what i should do i would appreciate it