I have an 08 F150 crew cab, 5.4l. When im driving about 20-40 mph and very lightly accelerating the transmission seems to slip. RPM's rev up and feels like it shifts hard. It also feel like it down shifts hard, but it doesnt do this every time. Very random. Can anyone give me an idea? Just hoping im not gonna need a rebuild since the truck only has 45,000 miles on it.

 

Almost sounds like the same thing thats happening to me. My scenario is this....I will be driving very lightly around 1200rpm, 40-45km/hr, shifts from first t second, second to third, then on third to fourth she revs up to 2000 quickly before shifting and the rpms come back down. My foot position does not change Im driving extremely lightly as well...Also seems to have some lag when letting go of the accelerator the rpms dont fall like they should, very slow to come down...

 

mine did the same thing at 80,000 and I had it rebuilt under warranty and it just went out again at 102,000 and still under warranty they decided to replace the whole trans this time so I hope it is good for awhile. If you have any warranty I would take it straight to the dealer and no wait at all.

 

hey man there is a TSB on it if you take it to the dealer they will flash it and update it

i havent had the problem since they did it... i also got the edge though. mine did it since day 1 brand new and i didnt know they could flash it and fix it until about 30k miles.

the truck was always at the dealer for oil/ maintenance since it was a lease before i bought it out and they still didnt update it until i spoke up... nice customer service...

 

yea there is a re-flash program i had it done too, it was like a tranny flare, i noticed it more so around 25mph-30mph, mostly around 28mph. take it to a dealership and explain its a flare in rpms around 28mph and they will understand what it is and re-flash the computer. it was free for me under warranty but i think its only like 40 bucks if you don't have a warranty...

 

mine is doing this too. going to take it in this weekend

 

good, mine hasn't done it since it was updated.... it was pretty annoying cruising through a small town around 25mph, then all of a sudden the truck would rev up and buck a lil

 

Mine is also having this issue. I will call my dealer today and have it re flashed. Mine is also around the 28mph area.
Just gotta say I'm pretty new to this forum and the late model f150s and this and all you guys are bad a#*

 

I agree I've learned so much about my truck in just a few days. Going to the dealer this aft to have a re flash done. I'll even show the guys how I found this out! Thanks so much for your insight!! Top notch!!

 

im looking for the tsb for you...