just took it on the highway. pressed "od off". no change in rpm or speed

 

No change at all??? That's strange, should have at least had TCC unlock for a few. I think....

What surprises me is, you aren't getting any O/D solenoid codes...... I am real curious why not.

 

it is strange. do u think im even in O/D at all?

 

No. No OD. Is fluid full (in Neutral and warmed up)?

Should be setting code. It isn't even trying or you would be getting 3-4 shift code.

 

And full of the proper fluid?


















ATF +4

 

i use atf+4. i warm the truck up doing light driving for 10 mins (no highway). I put it in park, shift through each gear (holding for 3 seconds), then leave it in neutral (running) and get my reading. its between add and full. no codes! lol

 

Older tranny, so not entiely sure. But it is not going into OD. Need to check solenoid, but I would look at wiring to tranny fist before dropping the pan.

 

but what about that shift from 48mph. it drops 200 rpm?

 

That's TCC. Normal.

 

ooo so its not locking up, just engaging?? if i try to go 60mph do u think i could get a code to come up?