Todd G.

AG2 is GM’s power front passenger seat adjuster. It is a thin code in our records — GM’s 2015–2018 Silverado guides list it with no description at all, and the 2019 wording is unverified.

AG1 is GM’s power driver seat adjuster. On 2015–2018 trucks GM says it is included and only available with AZ3 — it is not an upgrade you add to any seat.

AE7 is GM’s front 40/20/40 manual split bench. It tells you the seat’s shape and that it is manual — it does not tell you the material. GM lists it as both cloth and vinyl in the same year.

K34 is factory electronic cruise control. The code matters because it tells you the module, clockspring and brake switch are there — not just the buttons on the wheel.

UK3 is steering wheel mounted controls. If you are changing the radio, this is the code that decides whether you need a steering wheel control interface.

NP5 is the leather-wrapped steering wheel, the alternative to NK5. What it does and does not tell you, and the honest options for a worn rim.

NK5 is the standard urethane steering wheel. It matters in one situation: ordering a wheel, clockspring or airbag and needing to know which part the truck takes.

JL1 is the factory integrated trailer brake controller. GM’s own 2022 documentation says it requires Z82. How it differs from an aftermarket controller, and what to do on older trucks.

FE9 is not an option, it is a federal emissions certification. What it means for catalytic converters, EVAP parts and registering the truck outside California.

K05 is the engine block heater. The element and the cord are separate parts, which is why so many K05 trucks appear to have no heater at all.