The 2019 Cadillac XT4 is currently available with a single engine option, a 2.0-liter turbocharged four-cylinder gasoline unit making 237 hp and 350 Nm of torque. While an electrified version is likely to arrive further down the line, the XT4 looks set to get a four-cylinder turbo diesel as well. Despite setbacks such as the backlash against oil burners following the Dieselgate scandal and GM’s offloading of Opel, who was a development partner in the program, Cadillac seems determined to proceed with its diesel engine plan.

Secondly, one prototype’s tailpipe is a pretty strong indication that it uses diesel fuel. Whereas the gasoline XT4 has a single trapezoidal exhaust on each side, this particular XT4 prototype features a single pipe mounted on the left side and oriented towards the ground, as is typically the case with diesel engine exhausts. However, the second prototype features a dual exhaust layout (also on the left side) with straight pipes. Still, our photographers reassured us that both XT4s produced the unmistakable diesel sound at idle. And we trust them, although we would leave a margin for error.


Why the distinct tailpipes, then? Well, it could be simply because Cadillac is testing two different setups for the exhaust system. Another theory is the automaker is testing two different diesel engines or, more likely, the same powertrain in two states of tune. Or it could be something entirely different.

Either way, a diesel-powered XT4 seems to be on its way, despite Cadillac president’s previous statements. At the launch of the XT4, Steve Carlisle said the brand was re-evaluating its diesel strategy, adding that the program was on ice. If those two cars do indeed pack diesels, that means that GM’s luxury brand has decided to go on as planned. Now, it remains to be seen now whether the diesel-powered XT4 will be offered only in Europe or in North America as well.