How reliable is the 7.3 Power Stroke?

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Accepted Answer

The **7.3L Power Stroke** (technically the International Navistar T444E) is widely regarded as one of the most reliable and durable diesel engines ever put in a light-duty truck—often called "bulletproof" by enthusiasts and mechanics alike.

**Key Reliability Strengths:**

• **Mechanical Simplicity**: Unlike later emissions-era diesels, the 7.3L uses hydraulically actuated, electronically controlled unit injectors (HEUI) rather than complex high-pressure common-rail systems. This makes it more robust and easier to service.

• **Proven Longevity**: The specific truck you're looking at has **214,831 miles** and is described as running "tight and strong" with "no issues"—which is typical for these engines. Well-maintained 7.3Ls regularly exceed 300,000–500,000 miles, and many go even further.

**Known Weak Points (Manageable):**

• **Camshaft Position Sensor (CMP)**: The only semi-common failure point—this truck just had it replaced
• **HPOP O-rings**: The high-pressure oil pump can develop leaks over time
• **Glow plug system**: The relay and/or glow plugs themselves can fail (cold-start issues)
• **CPS (Injector) wiring**: The under-valve-cover harness connectors can loosen

**Maintenance for Longevity:**
• Regular oil changes (every 5,000 miles given HEUI system's oil dependency)
• Coolant changes (diluted coolant kills head gaskets in any diesel)
• Fuel filter changes

The fact that these OBS Fords are now "increasingly collectible" isn't just nostalgia—the 7.3L represents a sweet spot of power (210–250 hp, 425–505 lb-ft), fuel efficiency (15–18 mpg), and mechanical longevity that hasn't really been replicated in later emissions-era diesels.

Any other questions about this particular truck, or would you like me to find similar OBS diesels for comparison?

Lot 1FTJW36F7VEA15573: 1997 Ford F-350 XLT

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Lot 1FTJW36F7VEA15573: 1997 Ford F-350 XLT

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