Speaking of emissions, the only other mods on the engine itself are ATS Gorilla exhaust stacks with a high-flow diesel particulate filter. Both of those exhaust products are new for ATS, and the latter one is now in final testing. As of this writing, it's said to improve exhaust flow by 30 percent, and doesn't force the truck into regen as often.
It is obvious that diesels are getting more powerful from the factory. On his 6.4L, Sean is already creeping toward the 500hp mark with 1,100 lb-ft of torque. Making the most of the power gains are several ATS upgrades for the drivetrain, including a full-billet 5R110 transmission, a deep pan, Co-Pilot transmission controller, and a Five Star torque converter. The front and rear gear ratios are substantially lower as well-4.56 gears as opposed to 3.73 from the factory.
To take the project to even greater heights, Sean raised the suspension eight inches with a Fabtech lift kit, along with traction bars and a steering stabilizer. But that came with a downside. "The funny thing is that after I lifted the truck, I went to our first NSPA sled pull event and broke the rear pinion, which dropped down into the ring gear and tore it up. I also broke the left front axle hub. This was certainly a testament to the torque and horsepower the new '08 combination was making. That day my first Great White towed the '08 home." Hardly an auspicious start, but it's a good thing he had a backup rig.
After that, Sean took the suspension apart and cryo'd the front and rear axles as well as the pinon and ring gears. Then to add some flash, he painted his suspension ATS purple, and threw on an ATS rear differential cover, along with a set of 20x12 Revolver rims from Rev Wheels. He also painted the fender flares to match the two-tone scheme of the truck.
With all that done, what does the future hold for Sean's Great White Fords? Well, on the older 7.3L Power Stroke, Sean would like to build a common-rail system utilizing Duramax injectors. As for the 6.4L, he wants to make sure the research and development on the high-flow DPF is all sorted out before messing with the injector setup. Once he dives into the internals, he's thinking of developing head studs but won't reveal any detailed plot points until he's opened up the engine and seen what's inside. So stay tuned for Great White, Part III. DP
 A set of 38x15.50 Dick Cepek...  A set of 38x15.50 Dick Cepek Mud Countrys were mounted on 20x12 Revolver wheels to complement the 8 inches of lift. |  Sean monitors every aspect...  Sean monitors every aspect of the twin-turbo 6.4L. Here you can see a probe coming off the intake tube between the intercooler and the second turbo. |  Despite being lifted and riding...  Despite being lifted and riding on 38-inch tires, Sean told us that with the engine, and exhaust and tuning modifications, the truck went from 10 mpg to 14, and he's even seen 18 mpg on the highway. |
 Both the front and rear axles...  Both the front and rear axles were outfitted with ARB Air Lockers, and these switches on the dash turn on the compressor and lock in the front or rear lockers with the push of a button. |  Here you can see the dual-shock-with-reservoir...  Here you can see the dual-shock-with-reservoir suspension Sean went with, as well as the steering stabilizer. The ATS-purple front coil springs were painted by Sean while he had the front end apart. |  After breaking the rear pinion,...  After breaking the rear pinion, Sean disassembled the front and rear axles and cryo'd them for ultimate strength. This extreme cold treatment is something Clint Cannon, president of ATS, swears by. He's used it on his personal sled pull truck and claims this procedure reduces breakage and fatigue by as much as 80 percent. |