Ford took a big gamble by moving its best-selling F-150 pickup from a steel body to an aluminum one, but that gamble seems to have paid off with some of the best truck sales the automaker has ever seen. It’s also seen a lot of success in the adoption of its EcoBoost line of turbocharged engines, though one area the F-150 hasn’t made much progress is actual fuel economy, where diesel-powered rivals from both GM and Fiat-Chrysler have left it far behind.

That might soon change though, if a report from Autoblog is as accurate as we hope. Autoblog’s spy photographers caught an F-150 out testing with what they claim is the distinct sound of a Jaguar Land Rover-sourced diesel V6. This could help the F-150 crest the magic 30 MPG number, and give buyers a more efficient engine option than anything Ford currently offers.

The engine is most likely the new 3.0 liter “Lion” V6 from Jaguar Land Rover, which is slated for the Td6 models of both the Range Rover and Range Rover sport, offering a stout 254 horsepower and 443 lb-ft of torque. That’s more than both the 3.0 liter Ecodiesel engine found in the Ram 1500 and GM’s Chevy Colorado/GMC Canyon diesel twins, and it would even beat out the 420 lb-ft of torque offered by the gas-powered 3.5 liter EcoBoost V6.

But Ford isn’t going to stick a diesel engine into the F-150 simply for torque. No, this motor is about fuel economy, where the F-150 (26 MPG highway) has fallen behind the Ram 1500 (28 MPG) and Colorado/Canyon(31 MPG). In the Range Rover Td6, the 3.0 liter diesel motor earns a respectable 29 MPG despite having to haul nearly 5,000 pounds of British truck. With its lighter aluminum body, the F-150 could squeak across the 30 MPG threshold thanks to the Brit-sourced diesel…but that would also mean Ford would have to go back on years of dissing diesel engines in favor of its EcoBoost motors.

Is Ford ready for an about-face on diesel?