Ford f150 1999 4.2L V6 auto Transmission, erratic 3-4 shift hunting while ascending a very slight grade and mostly when cold. While keeping accelerator at a constant speed, it will jump back and forth between gears for a few seconds. Transmission fluid and filter changed and at proper level. Fuel filter, spark plugs changed, cleaned mass air flow sensor, and reset computer by disconnecting the battery just in case, but the problem still persists.
Tags: 1999, 34, 4.2L, ascending, auto, erratic, F150, ford, grade, shift, slight, transmission, v6