The Mistress

Donnie Yearsley had no idea what he was in for when he bought this 2008 GMC Sierra HD as his first diesel truck. But when he started adding power to it and sled pulling with it, the diesel addiction was in full effect.

Named The Mistress for sled pull competitions, Yearsley's LMM has been getting a lot of attention. He has finished at or near the top of the 3.2 Super Stock class in every event he entered. (He missed out on the points overall when his shift actuator blew up in a Salt Lake, Utah pull. He also lost a front driveline while pulling in Afton, Wyo., but still won his class there.)

Yearsley ran the GMC stock for 10,000 miles after buying it before he started cutting into it.

Working in Utah at the time, Yearsley and a friend installed a Pro Comp 6-inch lift in a shop on their own. That install took about 14 hours, he recalls.

He found a set of 20x10 Eagle wheels with a -24mm offset and wrapped them with 35x12.50R20 tires.

To get a little power back that the lift was robbing, Yearsley installed a Banks Six Gun tuner.

When Yearsley moved to Idaho later, he took the truck to Powerlabs Diesel, where he had them install an AirDog II lift pump and filtration system.

The truck's transmission came out and was taken to Adrenaline performance for a full rebuild using Adrenaline's proven method. The Allison was ready for more power now.

Next on the list was a TorqueMaster intercooler to increase the capacity of cool charge air for what Yearsley had planned.

Powerlabs ordered an MPI compound turbo kit and fitted a Borg Warner Turbo Systems' S400 charger with an 80mm compressor wheel to the kit.

The Borg Warner charger feeds to the stock LMM variable vane turbo, and pushes 60 psi of boost to the stock engine through an Adrenaline Performance inlet bridge pipe. They used a Banks intercooler pipe to let the charge air flow a little easier through the system.

A 4-inch Diamond Eye straight exhaust system, with no muffler, handles the massive amounts of air flowing from the exhaust.

To keep fuel flowing to the hungry rails, Powerlabs drilled out the fuel rail inlet fittings to 1/8-inch diameter and shimmed the fuel pressure relieve valve spring.

Yearsley and his friend Jeremy Richmond came up with an incognito mounting position for the DPS switch that controls the different EFI Live maps that Powerlabs tuned the truck with. The DPS switch sits in place of the factory cigarette lighter in the center dash console. Yearsley even cut off the end of the cigarette lighter and put it on the DSP switch to disguise it.

That's not the only custom work inside Yearsley's truck. He removed one of the center air vents and built a custom gauge pod to hold two Auto Meter gauges. It looks so clean Yearsley has been asked several times where he bought the kit. An Edge Insight CTS displays more of the truck's parameters.

Trucks get driven, and audio systems make that job fun and entertaining. Yearsley had Eminent HiFi do the sounds system with in-dash DVD and two headrest DVD monitors for the rear seats.

Outside the truck, Cognito traction bars keep the rear axle in line and a beefy 10-inch driveline hoop keeps the big Duramax safe and legal for pulling. Yearsley had a deep tranny pad powder coated to match the truck and recently added a custom grille by Royalty Core.

For now though, it's just more time with The Mistress.The Mistress now has 55,000 miles. Yearsley plans on doing more sled pulls. He hopes to add bigger injectors and a higher-flowing CP3 pump in the near future.

For information regarding the products used in this build, please visit Diesel Tech's Aftermarket Directory.