Why Did Ford Move Away from Navistar Engines?
If you’ve ever owned a Ford Super Duty truck from the late 90s or early 2000s, you probably remember the Navistar-built diesel engines. For years, Ford and Navistar (also known as International Harvester) were practically inseparable in the heavy-duty diesel world. So why did Ford eventually part ways and develop its own Power Stroke diesel engines?
It comes down to a mix of reliability concerns, changing emissions standards, and the desire for more control over engineering. In the early 2000s, Ford started getting hit with a wave of warranty claims and customer complaints about the 6.0L Power Stroke, which was designed and built by Navistar. Issues ranged from EGR cooler failures to head gasket problems—problems that cost Ford millions in repairs and, more importantly, dented its reputation for building tough trucks.
At the same time, stricter emissions regulations were coming down the pipeline. Ford realized that relying on an outside supplier made it harder to quickly adapt to these new standards. By bringing diesel engine development in-house, Ford could respond faster to regulatory changes and tailor its engines more closely to what truck owners actually wanted.
What Made the Power Stroke Diesel Engine Different?
When Ford introduced its own Power Stroke diesel engine—starting with the 6.7L Scorpion in 2011—it was a big moment. For the first time, Ford engineers had full control over everything from the turbocharger setup to the fuel injection system. The result? A cleaner, quieter, and more powerful engine that could compete with anything from Ram or GM.
One standout feature was the use of a compacted graphite iron (CGI) block. This material is lighter than traditional cast iron but just as strong, helping the engine handle higher pressures without adding unnecessary weight. Ford also moved the turbocharger between the cylinder banks, which improved throttle response and made servicing a bit easier. These changes weren’t just for show—they translated to real-world improvements in towing, fuel economy, and long-term durability.
How Did This Shift Impact Ford Truck Owners?
For many truck owners, the switch to Ford-designed Power Stroke engines meant fewer headaches. According to a 2022 survey by J.D. Power, customer satisfaction with Ford Super Duty diesels rose significantly after the introduction of the in-house 6.7L engine. Fewer breakdowns, better fuel economy, and more consistent performance—those are the things that matter when your truck is your livelihood.
It’s not just anecdotal, either. Ford’s Super Duty lineup has consistently ranked among the top three in heavy-duty truck sales since the 6.7L Power Stroke debuted. Fleet managers and small business owners alike have praised the engine for its reliability and lower cost of ownership over time.
Are There Any Downsides to Ford’s In-House Diesel Engines?
No engine is perfect. While the 6.7L Power Stroke has earned high marks for reliability, some owners have reported issues with the turbo actuator and NOx sensors, especially in high-mileage trucks. These are relatively minor compared to the widespread problems of the old Navistar 6.0L, but they’re worth keeping an eye on if you’re shopping for a used Super Duty.
Another consideration is cost. Developing an engine from scratch isn’t cheap, and some of those costs inevitably get passed on to buyers. But most owners agree that the trade-off—better reliability and performance—is worth it in the long run.
What’s Next for Ford’s Diesel Trucks?
Ford isn’t resting on its laurels. The company continues to refine the Power Stroke lineup, with recent models boasting even more power and improved emissions technology. There’s also a growing focus on hybrid and electric powertrains, but for now, diesel remains a cornerstone of Ford’s heavy-duty strategy.
Industry analysts from S&P Global Mobility predict that while diesel’s share of the pickup market may shrink over the next decade, demand for robust, efficient engines like the Power Stroke will remain strong in sectors like agriculture, construction, and towing.
The big takeaway? Ford’s move away from Navistar wasn’t about chasing perfection—it was about making smarter, more responsive choices for its customers. If you’re thinking about a Super Duty, start by looking at the post-2011 Power Stroke models. Make one change—like upgrading your maintenance routine or test-driving a newer diesel—and you’ll likely spot the difference by month’s end.
