8.0L Ford Power Stroke Diesel Rumors Appear to Be Nothing More Than Smoke

By Brett Foote - March 23, 2026

A DEF-free and ultra-potent 8.0L Ford Power Stroke diesel sounds like a dream, but in this case, it appears to be exactly that.

The Ford Power Stroke diesel engine has existed in various forms over the years, and in various displacements ranging from 3.0 liters all the way up to 7.3. Currently, the Super Duty line of trucks can be had with the newest, turbocharged 6.7-liter Ford Power Stroke diesel, which churns out 475 horsepower and 1,050 pound-feet of torque in standard guise, or 500 horsepower and 1,200 pound-feet in high-output form. Now, rumors suggest that the Super Duty’s forthcoming 2027 or 2028 redesign may include a brand new version of that diesel.

The rumors currently circulating around the web and social media suggest that the 2027 Super Duty will get a larger, 8.0-liter version of the Ford Power Stroke diesel, one that would churn out as much as 625 horsepower and 1,400 pound-feet of torque, which isn’t too hard to believe on the surface.

However, this rumor also claims that the new engine will ditch its Diesel Exhaust Fluid (DEF) system, used to reduce nitrogen oxide (NOx) emissions; albeit, while adding expense and complexity to modern diesel engines.

With recent regulatory changes taking place at the Environmental Protection Agency, it makes sense that some may speculate that such a change is going to happen, of course. On top of that, these rumors claim that the 8.0-liter Power Stroke will receive a new sequential turbo system to enhance its towing capabilities, with the big boost in displacement marking the return of the horsepower wars that automakers were once engaged in.

There are, as one might imagine, many reasons to doubt these rumors, however. For starters, the EPA is facing its fair share of legal challenges over its efforts to deregulate greenhouse gas emissions and loosen fuel economy standards, which may or may not prove successful. Then there’s the possibility that future lawmakers may opt to completely reverse those decisions if they do in fact become law, which would mean that Ford and its peers would then be forced to reverse course as well – a costly pivot, indeed.

We must also consider the fact that there’s no proof a new 8.0-liter Ford Power Stroke diesel is in development, either – these rumors are based on a supposed leak from an “internal engineering meeting” that “multiple engineers” have allegedly confirmed. It also claims that patents have been filed showing off a new diesel and sequential turbo design, but no such things exist at the moment.

Given the fact that the 6.7-liter Power Stroke continues to prove segment-leading in terms of output and efficiency – coupled with the fact that it’s unlikely Ford would opt to ditch its emissions systems amid ever-changing regulatory environments – we just have a hard time believing that it’s going to replace that engine with a larger, dirtier diesel, no matter how enticing such a thing might sound.