I have a brand new GM Factory Cold air intake($650) and extra filter($150) and KN filter cleaner and oil (ill install it for free, takes about a half hr) for all 2018 til now Silverado 1500's that is an upgrade for all motors except the 2.7L TurboMax, the turbo throws off the mass air flow sensor. Adds 20-25 horsepower. It fits the 4.3V6, the 5.3L, and the 6.2L engines. I had it in my 4.3L V6 until i sold it. I bought a new one for my 2.7L TurboMax gas engine and it threw a code related to the Mass Air Flow sensor but works just fine in all non turbo motors.
Fitment guide: Custom, Custom Trail Boss, High Country, LT, LT Trail Boss, LTZ, RST, SSV, WT all gas engines