M189
Inline-6- 189.988 3.0 L · 2,996 cc
170 PS
125 kW · 168 KM przy 5,400 obr./min
249 N·m
184 lb·ft przy 4,000 obr./min
Mercedes-Benz Luxury LWB · 300 SEL
Air suspension, a long wheelbase, and the 6.3.

Most W109s were long-wheelbase six- and eight-cylinder models — the alloy-block 300 SEL, the 2.8 that replaced it, the 3.5 V8 that outsold every other version, and the North American 4.5 — aimed at owners who wanted rear-seat space and chauffeur duty without stepping up to the hand-built W100. The 300 SEL 6.3 was something else: a Q-car capable of genuine supercar pace in a three-box suit.
Production over 1966–1972 came to 23,550 cars.

5 model designations across 1966–1972 — engines, chassis codes and production figures for the W109.
| Model | Lata modelowe | Zbudowano | Podwozie | Silnik | Skrzynia biegów | Razem |
|---|---|---|---|---|---|---|
| 300 SEL | 1966–1967 | 03.1966–12.1967 | 109.015 | 189.988 | 2,369 | |
| 300 SEL 2.8 | 1968–1970 | 02.1968–10.1970 | 109.016 | 130.981 | 2,519 | |
| 300 SEL 3.5 | 1969–1972 | 11.1969–09.1972 | 109.056 | 116.981 | 9,583 | |
| 300 SEL 4.5 | 1971–1972 | 05.1971–10.1972 | 109.057 | 117.981 | 2,553 | |
| 300 SEL 6.3 | 1967–1972 | 12.1967–09.1972 | 109.018 | 100.981 | 6,526 |
* Opublikowana liczba produkcji obejmuje każdą serię tego modelu; źródło nie rozbija jej dalej.

The engine and equipment milestones of the long-wheelbase, air-sprung 300 SEL.

Two injected sixes and three V8s — from the alloy-block M189 to the 6.3-litre M100 — as fitted to the W109.
170 PS
125 kW · 168 KM przy 5,400 obr./min
249 N·m
184 lb·ft przy 4,000 obr./min
170 PS
125 kW · 168 KM przy 5,750 obr./min
240 N·m
177 lb·ft przy 4,500 obr./min
200 PS
147 kW · 197 KM przy 5,800 obr./min
286 N·m
211 lb·ft przy 4,000 obr./min
198 PS
146 kW · 195 KM przy 4,500 obr./min
358 N·m
264 lb·ft przy 3,000 obr./min
250 PS
184 kW · 247 KM przy 4,000 obr./min
500 N·m
369 lb·ft przy 2,800 obr./min