A split year — the old WK2 body was still sold as the mainstream 2021, while the redesigned WL arrived first as the three-row Grand Cherokee L, so know which one you're looking at.

Because the mainstream 2021 is still the WK2, the 3.6L Pentastar's rocker-and-camshaft wear applies: a top-end tick that can become a misfire, with a teardown mechanic quoting $1,000 to $2,000 caught early and more if damage spreads, and Chrysler service bulletins documenting the valvetrain-noise condition across these years. Listen for the tick and scan for misfire codes as on every WK2 year.

The mainstream 2021's cheap-part wear items are the WK2's: brittle oil-filter housing, HEMI water pump, cracked thermostat housing — check for coolant loss — and the Uconnect touchscreen, which can misbehave. None is expensive if caught early. Confirm the screen responds cleanly and shows the backup camera.