Im a new Excursion owner I have questions?

Pretty classic problem, you can buy aftermarket actuators cheaper. They run in a serise so it could be the drivers side front. A good auto elec guy can tell you if it has to be all. Does it have a perf mod like a chip or prog.? I have an Edge programer and it was the only one that did not screw my truck up, I do get a check engine light if I really stab it with a trailer usually going up hill....it is an over boost code, I went and paid the $40 to find this out and it shuts off if you disconnect the batteries for a second or about 20 cycles of the key. If it has something I would take it out and get a baseline, drive it and then reinstall the mod. I tried 4 and had some that barely idled to lights flashing on the dash and all heck breaking loose with gages flip flopping. The chassis is different, the 7.3 is solid but the elec and mechanical of the truck can be a problem. I have 192K and I have not had any gremlins or weird things happen. Heck I am just replacing the batteries tomorrow, thats with lots of draw from lighs and constant drain till dead playing the stereo while working outside...thank god for those jump starter boxes....