You want a truck that keeps working when others give up, and this article walks you through eight diesel engines famous for just that — long life, solid parts, and simple serviceability. You’ll learn which engines tend to reach extremely high mileage with proper care and why they earn reputations for lasting a lifetime.
You’ll find practical context about durability, common strengths, and what to watch for when buying or maintaining one of these diesels. The article then breaks down each engine’s character, typical failure points, and maintenance habits that help them keep going.
Cummins 6BT
You’ll recognize the 6BT as the 5.9L, mechanically injected inline-six that earned a reputation for toughness.
Its simple, all-iron design and gear-driven components make routine repairs straightforward and extend service life.
Owners praise its torque and longevity in pickups, industrial, and marine use.
With proper maintenance—regular oil changes and valve adjustments—you can expect very high mileage from these engines.
BMW M57 3.0L
You’ll find the M57 a durable, torquey inline-six diesel that served BMW from the late 1990s into the 2010s.
Its common-rail injection and turbocharging give strong low-end pull and good fuel economy for long-distance drivers.
Routine maintenance matters: timely oil, fuel-filter changes, and air intake care extend its life.
Watch for turbo and EGR issues on higher-mileage examples, but well-cared-for M57s commonly run very high mileages.
Detroit Diesel Series 60
You’ll find the Series 60 in many long‑haul Class 8 trucks built from 1987–2011.
Its inline‑six layout and early electronic controls gave you better fuel economy and smoother operation than many contemporaries.
With proper maintenance these engines commonly reach very high mileages, and parts remain widely available.
Watch oil, cooling, and electronic systems closely to keep your Series 60 running reliably for years.
Ford Power Stroke 7.3L
You’ll find the 7.3L Power Stroke celebrated for durability and low-maintenance longevity in work trucks and tow rigs.
Its simple, robust design and widespread parts availability help many examples reach very high mileages.
You should watch for known weak spots on certain model years like injection pump or electrical issues, especially in late 1990s–early 2000s units.
A careful pre-purchase inspection and proper service history greatly improve your chance of buying a long-lived example.
Duramax LB7
You’ll find the LB7 — GM’s 6.6L Duramax from 2001–2004 — praised for simple, durable design.
It delivers strong torque and can reach high mileage when cared for, though early units had injector failures you should check for.
Plan for routine fuel filtration, a lift pump, and addressed injector work to keep yours reliable.
With sensible maintenance, an LB7 can serve as a long-lived workhorse.
International DT466
You’ll find the DT466 in many medium-duty trucks and buses, prized for simple, rebuildable design and long service life.
Its 7.6L inline-six layout gives strong low-end torque and straightforward maintenance that owners appreciate.
If you keep up with oil changes and basic repairs, the DT466 commonly goes hundreds of thousands of miles before a major overhaul.
Watch for injector return-line and emissions-electrical issues on later models, but parts remain familiar and widely available.
Volkswagen TDI 1.9L
You’ll find the 1.9L TDI praised for simplicity, fuel economy, and long service life. Many examples reach very high mileage with routine maintenance.
You can expect mechanical injection variants like ALH and PD to be durable, though Pumpe Düse (PD) versions may need attention to cam and injector wear. Keep up with oil changes, timing belt service, and proper fueling to get the most life from one.
Mercedes-Benz OM617
You’ll find the OM617 in many classic Mercedes diesels from the 1970s and 1980s, notable for simple, robust design.
Its five-cylinder layout and timing chain helped it run longer than many contemporary petrol engines.
Owners report high-mileage examples with careful maintenance; routine timing-chain checks and injector care keep it happy.
If you want a durable, easy-to-work-on engine for long-term ownership, the OM617 deserves serious consideration.
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