The Jeep Gladiator EcoDiesel Has A Worse Fuel Economy Than Advertised

What? There is already trouble for the 2021 Jeep Gladiator EcoDiesel? That was a little faster than expected. Upon testing the Jeep truck with the Ram 1500, EcoDiesel V6 engine, people discovered that it has a lower fuel economy than advertised. 

The 2021 Jeep Gladiator EcoDiesel has a lower fuel economy 

The folks over at TruckTrend got their hands on a 2021 Jeep Gladiator EcoDiesel Rubicon for an entire week of fun. That’s when they discovered that the diesel engine didn’t exactly improve the truck’s fuel economy. 

A red 2021 Jeep Gladiator sits atop of rocks.
New 2021 Jeep Gladiator EcoDiesel | FCA

To make room for the 5.1-gallon diesel exhaust fluid (DEF) storage tank, the EcoDiesel-equipped Jeep Gladiator has a smaller tank size. It only holds 18.3 gallons, but this shouldn’t cause a problem. 

The Jeep Gladiator Rubicon has an EPA estimated rating of 21 mpg in the city, 27 mpg on the highway, and 24 mpg combined. That should have provided a driving range of about 400 miles. However, TruckTrand logged 250 miles with an average of 18.82 mpg combined. That’s a lot lower than 24 mpg combined. 

Perhaps they really held the pedal to the metal, but the mystery is still at large. The Rubicon Gladiator is only rated at 1 mpg less than the Overland or Sport models according to the EPA, but that fails to explain coming up so short. 

Another mystery includes how their truck had less than 1,200 miles on the odometer, and it was halfway out of DEF. A 2,400-mile ranger on 5 gallons doesn’t make a lot of sense either. The diesel engine may not be worth it. 

Is the 2021 Jeep Gladiator EcoDiesel a good truck?

Yes, it’s a powerful truck that’s fun to drive. However, it might not be worth it. The EcoDiesel engine costs $4,000 more than the 3.6-liter V6 engine. Also, it’s paired with an automatic transmission. 

2021 Jeep Gladiator hauling a classic Jeep Wagoneer
2021 Jeep Gladiator | Jeep

To get it with a manual transmission, it costs another $2k. Then you’re up by $6k, and with such a low fuel economy with the rising cost of diesel, you may never generate fuel savings. However, if you really like driving it, then it could be worth it. 

How is driving the 2021 Jeep Gladiator EcoDiesel? 

The 3.0-liter EcoDiesel V6 engine provides 260 hp and 442 lb-ft of torque. It can tow up to 6,000 lb, which is lower than rivals, but not terrible. The acceleration is noticeably slower than the gasoline model, but it feels more confident when passing people. 

The Jeep Gladiator is a pickup truck version of the Wrangler.
Jeep Gladiator | FCA

Frustrating Problems With The Jeep Gladiator

Surprisingly, the EcoDiesel has smooth and quick gear shifts. Also, it has a quiet engine that’s hard to notice even with a soft top. The sound should be even quieter with the hardtop. But the road noise was higher at highway speeds. There is a noticeable humming for a while that lasts after turning the truck off too. 

The TruckTrend Team was able to do a little off-roading during the week with their Gladiator, but it mainly served as a daily commuter. Aside from being a little loud and bumpy, the Jeep Gladiator EcoDiesel was perfect for cruising.