Assuming you are talking about the 6.7L Powerstroke Diesel Engine:
The 6.7L Powerstroke was first used in the 2011 model year and is still being used in current model year trucks. This means that there isn’t a whole lot of data out there yet on how long these engines will last. However, we can make some educated guesses based on similar engines that have been around for longer.
Generally speaking, diesel engines tend to last longer than gasoline engines. This is because they are built stronger to begin with and they don’t have spark plugs or other ignition components that can fail over time. The 6.7L Powerstroke is a particularly robust engine, so we expect it to have an above average lifespan.
One study found that the average lifespan of a diesel engine is 1,000,000 miles. Another study looked at specific truck models and found that Ford trucks (which would include the Powerstroke) had an average lifespan of 14 years or 200,000 miles, whichever came first.
So based on these studies, we would expect the average Ford 6.7L Powerstroke engine to last for at least 200,000 miles before needing any major repairs or replacements