1976-1983 Mercedes-Benz W123 — MPG & Fuel Facts NO OFFICIAL EPA RATING

The EPA's public fuel-economy dataset only goes back to 1984 — the 1976-1983 Mercedes-Benz W123 (230, 280E, 240D, 300D) predates it, so there is no government-rated MPG number for this car anywhere, including here.

Estimated 16–28 MPG combined.

EPA guide rows and large owner datasets agree closely — about 16-19 US mpg for the gas 230/280E and about 22-28 for the diesels — so the wide range reflects the gas/diesel split, not source disagreement.

This is our estimate, not an EPA rating — built from the period road tests, marque-specialist guides and corroborated owner reports cited below, hedged where sources vary. Treat it as a ballpark for planning, not a spec to rely on.

US W123s: gas 230 (2.3 four, 1976-78) and 280E/280CE (DOHC 2.7 six); diesel 240D (2.4 four) and 300D/CD/TD (3.0 five-cylinder, naturally aspirated, then Turbodiesel from 1981). Nearly all US cars were automatics; the 240D could be had with a 4-speed manual — which is where the famous '30+ mpg 240D' stories mostly come from.

From the 1977 EPA Gas Mileage Guide (the first US W123 year): 240D at 25-26 city / 30-34 highway / 28 combined; 300D at 23/28/25; 230 at 17/21/19; 280E at 14/19/16. Pre-1985 test method — optimistic, especially on the gas cars.

The modern fueleconomy.gov database catches the very last W123 diesels: the 1984 300D/300CD Turbodiesel is rated 21 city / 23 highway / 22 combined under the revised, more realistic methodology — a good anchor for real-world turbodiesel expectations.

Owner-logged data corroborates: Fuelly's 240D page (69 owners) averages 23.4-27.9 US mpg across 1977-83 model years, its 300D page shows 22.2-26.0 for W123 years, and Benzworld threads report about 24 city / 28 highway for healthy naturally aspirated 300Ds.

Sources: EPA 1977 Gas Mileage Guide (Mercedes-Benz rows, read from scanned government booklet) · fueleconomy.gov — 1984 Mercedes-Benz 300D/300CD Turbodiesel (revised-method EPA rating) · Fuelly — Mercedes-Benz 240D owner logs (69 owners) · Fuelly — Mercedes-Benz 300D owner logs · Benzworld forum — 'Fuel consumption of W123 240D and 300D'

All classics Search Mercedes-Benz W123 (230, 280E, 240D, 300D) on FuelFacts (in case a later model year is in our 1984+ EPA data)