And this time, they're saving ’07+ Jeep Grand Cherokee CRD owners money at the pump. Its Eco tune for the Mercedes-Benz 3.0L V-6 engine is said to increase responsiveness, smooth out shift points, shave an entire second off 0-60 mph times (8.3 seconds stock vs. 7.3 seconds tuned), and its customers are reporting at least a 20 percent increase in fuel economy (2-4 mpg). Better yet, all of this is accomplished with the DPF intact and regeneration cycles not being altered.