The Jeep Grand Cherokee SRT8 and the Chevrolet Trailblazer SS have no reason to exist. Both get horrendous gas mileage. Both are faster than any 4500-plus-pound rolling bricks ever should be.

The 2018 Jeep Grand Cherokee Trackhawk shares the majority of its interior with its fellow Grand Cherokee stablemates, which isn't a bad thing but it's not quite as nice as other high-end SUVs.

Which is why we're here comparing a pair of new, high-powered sport-utility vehicles: the Chevrolet TrailBlazer SS versus the Jeep Grand Cherokee SRT8. Jeep's Grand Cherokee, already a powerful ...