Mercedes‑Benz E‑Class S124 Engines — The Complete UK Guide
Every engine fitted to the S124 estate — from the 72hp OM601 diesel to the 220hp M104 six‑cylinder and the rare AMG 3.6. Real UK costs, classic‑car running realities, and the bulletproof diesel‑six legend that defines this generation. Backed by real UK S124 enquiries in 2025 [MB‑VERIFIED].
Explore S124 Engines
Mercedes‑Benz E‑Class S124 Engine Codes — The Complete Database
Overview
Mercedes‑Benz E‑Class S124 — Overview
The S124 is the estate bodystyle of the Mercedes‑Benz W124 range, launched in October 1985 as the load‑lugging counterpart to the executive saloon.
It shared the W124's advanced engineering — including one of the lowest drag coefficients of its era, multi‑link rear suspension, and a modular engine family spanning four, five and six‑cylinder configurations. A major 1993 model‑year update brought the E‑Class naming convention and the M111 and M104 engine families, making this generation a genuine two‑era classic under one body code. The S124 remains one of the most cherished estate cars ever built, prized for its legendary build quality and the bulletproof diesel engines that routinely exceed 300,000 miles.
Key Facts
Platform
Mercedes‑Benz W124
Predecessor
S123
Successor
S210
Sibling body styles in this generation
W124 Saloon, C124 Coupé, A124 Cabriolet
Market Intelligence
The W124 range (saloon and estate combined) generated real UK engine enquiries in 2025 [MB‑VERIFIED], with the OM603 diesel and M104 petrol commanding the strongest specialist interest among classic Mercedes enthusiasts.
Best & Worst Engines
Best Diesel Overall
OM603 3.0‑litre six‑cylinder diesel (300 TD, 110hp / 300 TD Turbo, 143–147hp)
“The cast‑iron block, pre‑combustion chamber diesel six that built Mercedes' reputation. No turbo on early cars, no DPF, no EGR — just mechanical fuel injection and a documented 500,000‑mile lifespan. Head gasket issues are virtually unheard of with proper coolant maintenance.”
Who it's for: buyers who want the most durable diesel engine Mercedes ever built.
Best Petrol Overall
M104 3.0‑litre 24‑valve six (300 TE‑24, 220hp)
“The multi‑valve evolution of the M103 — smoother, more powerful, and with a genuine 220hp that transforms the S124 into a rapid estate. The M104 is a stout motor that benefits from a well‑documented maintenance regime.”
Who it's for: enthusiasts who want six‑cylinder refinement and genuine performance.
Highest Risk
M102 2.0‑litre carburettor four (early 200 TE)
“The carburettor is the weak link — early cars suffer from cold‑start and idle issues as the Stromberg unit ages. The later KE‑Jetronic injected versions are more reliable but still not as durable as the M111 that replaced them.”
Who it's for: buyers on a tight budget who are comfortable with classic‑car carburettor maintenance.
Most Expensive Failure
M104.992 AMG 3.6 (E 36 T AMG, 272hp)
“The rarest S124 engine — a 3.6‑litre hand‑built AMG unit with 272hp. Parts are scarce, specialist knowledge is limited, and a full rebuild is a five‑figure bill.”
Who it's for: collectors and AMG enthusiasts with deep pockets.
Best Value
OM602 2.5‑litre five‑cylinder diesel (250 TD, 90hp / 250 TD Turbo, 126hp)
“The five‑cylinder diesel is the Goldilocks engine — more refined than the four, more economical than the six, and the turbo version delivers 126hp with genuine usability. The OM602 is bulletproof and parts remain widely available.”
Who it's for: buyers who want diesel durability without the six‑cylinder's running costs.
Most Overlooked
M111 2.2‑litre four (E 220 T, 150hp)
“The post‑1993 M111 is one of Mercedes' most durable modern four‑cylinders — 16 valves, 150hp, and none of the carburettor or early KE‑Jetronic complications. It's the sensible choice in the petrol range, often overlooked in favour of the sixes.”
Who it's for: buyers who want modern petrol reliability without the six‑cylinder's fuel consumption.
Mercedes‑Benz E‑Class S124 — Ownership Economics
The S124 rule
A £2,000–£4,000 OM603 recon against a £3,000–£8,000 S124 sits at 25–133% of the car's value — on a high‑mileage £3,000 example, that brushes the 70% Mercedes‑Benz threshold. Against a well‑kept £8,000+ example, the same recon drops to 25–50% — a routine repair decision, not a financial one. Value the car and its body condition first.
Common Problems
S124 Engine Replacement Costs — By Engine and Condition
Core Variants
Core Variants
Scope note: All variants listed are S124 estate only. W124 Saloon, C124 Coupé and A124 Cabriolet share most of these engines but are covered on their own Generation Pages, since fitment and production years vary by body style.
Market Intelligence
Most Requested E90 Engines (2025)
Most Requested E90 Variants
Average E90 Replacement Cost
Most Common E90 Failures
FAQ
Why UK Mercedes‑Benz E‑Class S124 Owners Trust MercedesEngines.uk
Trusted S124 Engine Suppliers
every garage and engine rebuilder in our network is vetted, rated and reviewed by real S124 owners, as part of the Engine Finders network.
Compare S124 Engine Replacement Companies
see prices, warranty terms and supply‑and‑fit options side‑by‑side before you commit.
UK Engine Replacement Services for S124
covering every variant from 200 T D to E 36 AMG, with supply‑only or full supply‑and‑fit available nationwide.
Find the best Mercedes‑Benz E‑Class S124 engine replacement UK drivers rely on. Compare real prices from trusted specialists on EnginesMarket today and get back on the road with confidence.
