I've noticed a lot of people stating to use only Mopar parts for certain fixes (crank and cam sensors, oil sending unit). Why do aftermarket parts never work on Jeeps? Is it a conspiracy? Or is it the fact that aftermarket parts just suck *****?

Mopar rules!! Parts store has Chinese junk that don't last.

It's best to use OEM parts for every brand, not just Jeeps. OEM stuff fits better and is vehicle specific. Aftermarket stuff can be made to fit a variety of vehicles.

The big thing is most of these parts are micro circuits with electronic components and hall-effect switches. Quality of construction is important and most after-market companies aren't as critical about their components. When I changed my oil pressure sensor, it broke taking it out. I was amazed to see a printed circuit board and piezoelectric crystal in it.