PLEASE help! my overdrive will not kick in!

[8lugs8feet]

ok so on my way home from my in laws today, OD was working just like always. drove through town and when i turned to get on highway the truck shifted through all four gears but once i got to 45-50 OD would not kick in. so had to drive the truck at 45 home 2 and a half ours. what could be problem?? i mean its like no overdrive is there at all. when you do get it to 50 or 60 mph and let of the gas no decel just like you were rolling in neutral. please help this is DD and with the winter weather i need this 4x4. thanks to all

[08pwrstrokr6.4]

sounds like the torque converter isnt locking up

[8lugs8feet]

that sounds viable. is there not anything electrical that i could check? like a relay or solenoid? its really weird like there is NO overdrive. it gets to 4th and tops out.i tried to pull some codes but no avail.

[8lugs8feet]

sunday bump! anybody have any suggestions? trust me if i could afford it i would replace my trans all together with a bts but $$$$ is low with raising my 2 teenage sisters

[FordNutz]

I guess I don't understand,

If it shifts four times, you are getting OD but no lock-up. You said that you had to drive home at 45. That means you might not be shifting into OD. The OD piston snap ring could have popped off (common), or you have electrical issues.

[8lugs8feet]

yeah i counted from a dead stop 4 shifts but when i get up around 45 it just keeps revving. it will go faster but i redline around 65 and there is no other shift. the 4r100 is a 4spd transmission with OD correct? or is 4th gear my OD?

[08pwrstrokr6.4]

od is actually your tc locking in if i understand drive lines correctly

[8lugs8feet]

UPDATE. didnt drive the truck at all sunday the 2nd. started it up and drove it the 2 miles to work just easing it down the road and decided to kick it up around 50mph and boom it locked in and has the times ive driven it since. i havent taking it to interstate spd yet but what do you think that means??? TC going out?

[rwhite8]

might be trans computer issue

[7.3eleanor]

Is the O/D light flashing