2007 Chevrolet 3500 - Big Iron

Mount Logan Off-Road in Logan, Utah, is well-known for its stunning project vehicles, including buggies, Jeeps, prerunners, and desert race trucks. The company also attends most trade shows around the country. To get his products to the trade shows and vehicles into the dirt, John Williams, owner of Mount Logan Off-Road, builds 1-ton 4x4 trucks that can haul big loads. John says he chose this '07 Chevrolet 3500 Classic dualie 4x4 because he didn't know how the new emission diesels were going to run and had put many miles on an almost identical '06 that had performed flawlessly. The new '07 was equipped with the Duramax V8 diesel and Allison six-speed automatic. John left the front and rearends stock with 3.73 gearing, and the factory limited-slip in the rear does fine keeping the truck moving in low-traction situations.

The Mount Logan trailer is a 48-foot enclosed Motiv hauler that works well on the pavement and also holds up well when being towed on dirt roads to staging areas for races, competitions, and other events. It's a heavy-duty trailer that's also heavy - especially when loaded with two vehicles and all their accompanying "stuff." The big Chevy needed to be tough enough to haul this load.

Although the Duramax performs well in stock configurations, it has the potential to work even better. A Bully Dog downloader with Performance Management Tool (PMT), a Bully Dog air intake kit, and a Bully Dog 4-inch stainless exhaust system including new down pipe really woke up the GM diesel and allows it to perform to its maximum potential. The PMT in the cab allows John to quickly switch between power settings and also displays a variety of gauges and information at the touch of a button.

For suspension, John chose the Tuff Country 4-inch IFS kit for its quality and performance. In back, Air Lift heavy-duty airbags augment the factory leaf packs. Bilstein shocks ride at all four corners. We not only photographed the truck towing the Motiv trailer but also rode in it in the dirt and can report the suspension is great. You'd think a suspension that can handle all this big iron would ride pretty stiffly when unloaded. Not so. The Tuff Country suspension was surprisingly supple and handled rocks and dirt well. It also rode better, in our opinion, than stock on the pavement. The suspension allowed John to mount six 295/75R16LT BFGoodrich All-Terrain T/AKO tires on 16-inch KMC XD Series Rockstar alloy wheels.

Inside, besides the Bully Dog PMT, John has a JVC in-dash DVD player and a Lowrance iWay 350C GPS nav unit so he'll be entertained on long trips and won't get lost while his passengers are watching an in-flight movie.

As we were passengers in this big truck, we can report that the dualie, while pretty big for off-road forays, can handle mod-erately rough dirt roads with ease and fits places we couldn't believe! On the pavement, Mount Logan's Big Iron Chevy performs flawlessly and does what's asked of it - hauling big loads, or just plain hauling.