Jeep's 1980s era 2.5-liter four-cylinder engine didn't have a ton of power behind it, but it was incredibly reliable, something it's still known for today.

See detailed specs, features, packages and dimensions by trim level for the 2002 Jeep Grand Cherokee.

If you've been around for nearly two decades like this piece of machinery, there's going to be good and bad years. Learn more about the Jeep 4.0L engine here.

We're rebuilding the 4.0L engine in this 2005 Jeep Rubicon Unlimited. We added new JBA headers for better exhaust flow, an Airraid throttle body spacer, and a cold air intake setup from Airaid all ...

600HP, turbocharged, 4.0L jeep inline-six.Naturally aspirated, this stroker engine pumped out 312 hp at 5,400 rpm and 330.5 lb-ft of torque at 4,400. But once the turbo and air-to-water ...

Chief engine builder Keith Newcomer has been pushing the limits on the 4.0-liter straight-six for years, employing modern tech to see just how many horses he can squeeze out on the dyno.

No better way to quadruple a two-valve Jeep engine's horsepower like 20 pounds of boost and water-meth injection.