RPO

Z85 is GM’s standard handling and trailering suspension. If your label has Z85 and not Z71, this is the truck you have.

VYU is GM’s Snow Plow Prep Package. GM’s 2016 special-applications document lists all ten components — spring rate, oil cooler, alternator and more.

Z71 is GM’s off-road package. What it actually includes changed with every generation — here is what the factory documents say, year by year.