| Adding the H2008 module improved mileage more than 20% over the last two months. This makes Dr. Performance's module even more attractive to the average mileage seeker, especially with the 6.4L's bad-mileage wrap.
Losing the factory warranty makes a lot of truck owners out there cringe when they consider modifying their diesel. However, they also tend to cringe when they glance at the mileage their new, emissions equipment-laced rig is getting. But, life can still be enjoyed, mileage can still be increased, and additional power can still be made without having to classify your new $50,000 truck as an "off-road" vehicle.
Aside from its innovative work on a 13-second 6.7L Dodge Ram, Dr. Performance has hopped on the DPF-friendly bandwagon for the 6.4L Power Stroke. We recently took an '08 Super Duty to D.C. Performance's dyno with two of Dr. Performance's power modules. The first module we tested was its early 6.4L model (PN 42008), which had increased our Super Duty's mileage from 15 mpg to as high as 18.8 mpg. Then, we plugged in its newest module (PN 42008HO), and compared the two.
| As you can see, we weren't able to find out what kind of power the truck was making past 2,650 rpm. However, when comparing to stock, the H2008 module gained 40 hp and 75 lb-ft at 2,650 rpm, while the H2008HO module gained 44 hp and 86 lb-ft over stock at the same rpm.
Driving ImpressionsBoth modules turned our '08 Super Duty into a different animal. There is definitely a seat-of-the-pants improvement compared to stock, and the truck gets up to cruising speed effortlessly. Throttle input is more sensitive, turbo spool-up is quicker, and mileage increased to boot. With the H2008 module installed for the last 5,000 miles, city fuel economy increased from 12 to 15 mpg, and highway cruising improved from 15 to roughly 18.5. The one drawback on the H2008 module was that, over the course of two months, it entered a subtle limp-mode on three occasions. These instances occurred on the highway. The truck would involuntarily shut off cruise control, and only provide adequate power to get us where we were headed. After shutting the truck off at our destination, the truck's computer would reset, and the problem would be gone once the truck was started again. According to Dr. Performance, a loose connection is the only way this could happen. So we made sure to check and re-check our connections for tightness when installing the new module.
