My 7.3 isn't chipped (far as I know at least). I believe Ford SVO reprogrammed the ECM while they had it in 1998. I have the OEM rubber plug in the port above the e-brake pedal. I know the transmission has be remapped because everything inside was changed and it shifts hard and quick all the time.
I've read quite a bit of bad press on aftermarket chips and how they advance the injection timing and what that eventually does to the engine and I'm planning on my truck outliving me so no chips on mine. Mine hauls butt the way it sits.
Mine is hard on U joints and carrier bearings but I think it's because of the abrupt way it upshifts.
Been so long since I had a payment book I wouldn't know what to do with one....
Just put it to bed for the winter. Added biocide to both fuel tanks and Archoil fuel additive and topped them off and fogged the fender wells and wheel arches with oil. Have the battery tender on it and it's sitting next to the camper in a heated garage. It won't come back out until April other than starting it every few weeks and circulating the oil. In the spring it's getting all new hoses, new serpentine belt and a spin on water filter with a potassium permagnate block in it. That will save me from adding DCA4 every few months and using test strips to check the silicate levels.