Color combination, special two-tone, Big Dooley

Years 1983–87 Models 1 Factory citations 5

Also documented for Chevrolet

Documented applications

Sierra — Square body (1983–1991)

1983–1987 Factory-verified

shared platform code; cited from the square-body C/K pickup kits; only in: 30 series fleetside with R05 dual rear wheels

GM Heritage factory kit — 1983 Chevrolet Truck, p.37.
GM Heritage factory kit — 1984 Chevrolet Truck, p.35.
GM Heritage factory kit — 1985 Chevrolet Truck, p.34.
GM Heritage factory kit — 1986 Chevrolet Truck, p.167.
GM Heritage factory kit — 1987 Chevrolet Truck, p.51.

This page aggregates every documented appearance of ZY9 in the GMC reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.