Hello everyone,
I have a 2002 f350 SRW 7.3 truck with 140k miles on it i bought it with 102k on it and it has always had a bit of a firm shift if you want to call it that others may call it rough or hard. But the catch is its only sometimes. When im driving i might not feel it shift at all then other times i feel it just a little but then sometimes its horrible and reminds me of when my EBPS was clogged with the tube i had horrible hard shifts when that was plugged up. The EBPS isnt clogged i bought a new one from diesel o rings and cleaned the origonal tube out i actually just had that back off the truck maybe a month ago thinking that was the problem again and its not. So im wondering now maybe i got a deffective EBPS? Any ideas how to test this thing? because when i cleaned what was in it out with brake cleaner the truck did run better atleast it seemed to. i got a small powergain back. But now its back to normal shifting hard here and there and when it shifts hard the truck seems to run like a dog just feels like it takes forever to get up to speed. Or maybe im not giving it enough go pedal? i only run the rpms up to 2200 max empty because i dont really see a reason to go past that. Would the valve body have anything to do with these shifts? Also what controls the downshifting? I was towing a little honda on a trailer a few months ago and when i got to a hill i had to give it atleast half throttle to knock it out of overdrive and get it to drop to 3rd so i didnt feel like i was bogging the truck down going up a decent hill. Thats another thing is sometimes it will downshift fine then other times it like it does not want to come out of overdrive for the life of it so i have to just keep giving it more pedal to get over the hill. One more thing i have noticed is when im coasting to a light and it falls out of overdrive the rpms will fall to about 1100 then float there for a second then fall the rest of the way to an idle. is that normal? When i say overdrive i mean the TC is locked according to my edge evolution. hopefully i dont confuse anyone there.

 

im reading on other forums that my downshifting problem could be the valve body? i do not completely understand how a transmission works though so i have no clue if that true.

 

No, it isn't the valve body. The computer controls when it shifts.

The hard shifts are probably an engine problem. It sounds like the engine isn't making the correct power, and that will cause harsh shifts. Fix the engine and the trans will be fine

 

ok thanks. i will probably have to take the truck to a shop and have them plug it into a fancy computer because from what i see i cant find anything else wrong with the truck i replaced the up pipes and a few other things. i may have an injector going? sometimes the truck runs great other times its poor on power no rough idle or anything though.