General Motors option code
M4 — Four Note Horn
M4 (Four Note Horn): a General Motors factory option code recorded on 1 model across 1973–1976, with installs and price where a source states them.
1 model · 4 model years · 4 sources
Every sourced appearance
| Year | Model | As named that year | Price | Installs |
|---|---|---|---|---|
| 1973 | Buick Riviera | Four Note Horn order code (Buick option code) | $15 | Unknown |
| 1974 | Buick Riviera | Four Note Horn order code (Buick option code) | $16 | Unknown |
| 1975 | Buick Riviera | Four Note Horn order code (Buick option code) | $16 | Unknown |
| 1976 | Buick Riviera | Four Note Horn order code (Buick option code) | $17 | Unknown |
Every row traces to the source it links from on that model's own year page; this table only collects them in one place.