D1 / D4 / D5 ● Confirmed

Buick · Regular Production Option

Sonomatic AM / AM-FM stereo / AM-FM radio

Years 1970 Models 1

Documented applications

Full-Size — LeSabre / Electra / Wildcat →

• 1970 ● Confirmed

  All full-size

This page aggregates every documented appearance of D1 / D4 / D5 in the Buick reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.