Large and in charge, this Duramax was just the kind of truck for what we wanted to see at the 2017 SEMA Show. Rockstar Performance Garage built it, and, as our neighbors here at our Murrieta, California office, we did the neighborly thing and spoke with owner Nicholas Ashby to learn more about the truck.

Nicholas and his crew are no strangers to big off-road builds, let alone SEMA builds. This year alone, the team had over a dozen vehicles on display at the SEMA Show.

The truck used a custom Knapheide bed to mount a Polaris RZR in the rear.

“The vision behind this truck was something that was over-the-top, but also made your life easier,” said Nicholas. “I was in the meeting with Cass Alves, one of the owners of Scosche. I proposed that we use his truck, an $80,000 Denali, and find a way to put a Can-Am Maverick safely on the back. Eventually, he agreed.”

The 2500HD was built over the course of a month in 2016. For the bed, Nicholas went with Knapheide. “I was like, ‘Alright, thanks for giving this to us, now I’m gonna cut it up,'” he joked.

Nicholas’ goal with the bed was to get it to mount a UTV without having it sit too high, where it would greatly affect the center of gravity. This would make it still usable for off-roading and practical for hauling around a UTV.

I love the guts of builds, because that’s where you get to understand what the build is about. – Nicholas Ashby, Rockstar Performance Garage

But that wasn’t an easy task, as Nicholas made clear. “The UTV is eight feet long, and the bed is only six feet long,” he said. “The entire system is designed so that the UTV is winched up, rather than driven up. It also had to sit as low as possible.”

With a 1,000-pound UTV and 1,800-pound bed, it was up to the Hellwig air suspension to keep things afloat in the rear. “We made brackets with 3/8-inch steel to mount the air bags,” said Nicholas.

Backing up the air bags were Atlas leaf springs and a BDS 5.5-inch coilover conversion lift kit. For performance, the truck had a Mishimoto intercooler, K&N intake, and Edge CTS2 tuner.

Lighting elements were from Bulldog LED Lighting, with headlights provided by Spyder. The face of the Duramax was bolstered by a Royalty Core grille and Addictive Desert Designs Stealth bumper. 20-inch KMC Rockstar 3 wheels and 40-inch Mickey Thompson MTZ P3 tires offered the right mix of style and performance. What’s more, Titan Fuel Tanks sent along a 50-gallon fuel tank to give the truck greater range.

The Scosche Duramax was built in a month. It was designed for a UTV to mount securely in the bed, while also mitigating negative effects on the truck's center of gravity. Photos: Rockstar Performance Garage

As for Scosche, the electronics company donated a MagicMount Pro phone mount, ReVolt Dual USB charger, iPad dash mount, and EFX audio.

Nicholas is proud of the work he did on the truck, especially when compared with other SEMA truck builds. “It feels great to know that the truck I built just did two days on Hell’s Revenge in Moab, and it wasn’t just fancy camera work,” he said. “The truck was actually out there, getting air, going over rocks, and being used like a workhorse.”