The Jeep Wrangler EcoDiesel has stood out in the lineup for several reasons. It may be down on power to it’s four cylinder and Pentastar V6 siblings, but it more than makes up for it with an impressive 25 combined MPG and 442 lb-ft of torque. Until the plug-in-hybrid Wrangler 4xe and Hemi V8-powered Wrangler 392 come along, it’s actually the most efficient and torquiest engine in the lineup. But while Jeep’s claimed stats seem to prove the Wrangler 392’s torque figures will beat those of the EcoDiesel, a recent Dyno test of the Wrangler EcoDiesel may imply otherwise.
The test was posted on JL Wrangler Forums along with plenty of information, photos and videos. It was conducted on a supposedly bone stock Jeep Wrangler EcoDiesel on a Mustang dyno, where it measured 547 lb ft at the rear wheels. Mustang dynos typically calculate about 20 percent drivetrain loss from the crank in 4WD vehicles, meaning the astonishing torque reading is likely under what the engine is actually making. This puts the torque at the crank somewhere near 560 lbs-ft of torque, around 200 more than the manufacturer claimed figure.
If the test is accurate, that is.
The post has sparked doubt in the Wrangler community, with many rightly pointing out the strange power figure. In the video, the torque does indeed rise to that 547 lb ft reading, but the horsepower only hits a measly 61. Obviously, the Wrangler makes more than 61 hp, but if this reading is so off, it’s fair to assume the torque could be skewed in the opposite direction. Other commenters have gone as far as to say the owner is hiding a tune on the Wrangler, who insists that it’s stock (perhaps to avoid any inquisition from authorities), and the dyno was run correctly to the best of their knowledge.
Unfortunately, the poster says never received an email or paper copy of an output graph even after asking for it in a followup, which is usually commonplace when getting a dyno reading. The forum member still claims the facility and company, World Motorsports, is one of the most reputable in LA, however.
There’s enough uncertainty that we aren’t completely on board with the idea that the Jeep Wrangler EcoDiesel really makes 547 lb ft of torque from the factory. While true, automakers are known to downplay engine outputs from time to time, it’s never by this much, especially when torque is a selling point for the EcoDiesel. Then there’s the fact that manufactures have more sophisticated testing measures to get accurate readings.
There’s probably no intentional deceit in this test, and the forum post about it, but it’s clear something doesn’t add up, and it’s unlikely the EcoDiesel’s torque figure is really this underrated. Our guess is this is an equipment malfunction the dyno company doesn’t feel like owning up to, and the Jeep owner didn’t catch until the comments poured in.
For additional proof, we’re going to need more Jeep Wrangler EcoDiesel dyno videos.