Overdrive problem 5r55e

[RangerChick]

i have an 04 ranger xlt thats had a motor and tranny swap to an 05 4.0 bored and stroked to 4.7 and an 06 5spd auto tranny. everything was fine for the last 5k miles or so but about a month ago my "O/D OFF" light began flashing and i lost overdrive completely. it is also shifting hard and late thru the remaining gears now. any suggestions? i need help yesterday!

 

[BrooklynBay]

Welcome to this forum! The flashing overdrive light is a way of telling you that there is a code stored which needs to be read. It's like a check transmission light. Don't continue to drive it this way. It's in FMEM or "limp" mode.

 

[RangerChick]

we tried to pull the code and there is none to pull even with the light flashing...also the problem is not constant...it is only when the truck warms up, when cold it is fine

 

[BrooklynBay]

Not all scanners are capable of reading these codes. It's possible that the scanner used couldn't read the codes. A flashing overlight light represents a code stored in the PCM.

 

[RangerChick]

the scanner does read tranny codes, we use it all the time for that, and there are no codes stored in the pcm

 

[RangerChick]

we have pretty much narrowed it down to a problem in the wiring harness as this is a remnant ofthe original 3.0...the 4.0 wiring harness is on order from ford even though we have already made the existing harness match the one of the 4.0