[jsb5717]

What year is your truck? My experience is with diesel trucks but currently have, and have previously used, tuners. My 2000 F250 diesel had a 4 speed tranny...it was constantly trying to upshift at the wrong times. The tuner I bought was a Superchips that plugged into OBD port. I set it to Heavy Tow and it made a huge difference since it changed the shift patterns to better hold it's RPM's in the long uphill climbs.