Pulling my hair out on this shifting issue. Changed gov solenoid and transducer twice, seems to shift better for a short time or when cold sometimes. Bands were adjusted, no major wear particles were found in the pan, and has fresh oil and filter.

I found that when it does not upshift from either 1-2 or 2-3 if I place the trans in neutral then back into drive it shifts into the appropriate gear for the speed and RPM I am at. Thanks in advance.

 

Check the connector at the trans, make sure there isn't any exposed wire, and that the contacts are clean, and tight.

 

I would guess may the kick down lever, cable or actuator maybe hanging up. Could also be the kick down assy on the valve body Have you had any transmission work done on this truck before?

 

I checked wires and no bare or abrasions, all seem intact and no issues with the plug.

 

I did replace the trans lines and seemed to be more of an issue after that. Perhaps tugging on the actuator cable to get lines around it could have caused an issue? Thoughts?

 

Think I would disconnect the cable at both ends, and make sure it moves freely in both directions, and also make sure the lever on the trans moves freely. If it's good, reinstall it, and make sure it is adjusted properly, see what happens.