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.

The Bilstein shocks are dirty,...        read full caption The Bilstein shocks are dirty, but they work. At least we can tell that Mount Logan keeps everything lubed correctly.	The big Chevy's torsion bars...        read full caption The big Chevy's torsion bars are easy to adjust. Note the rocker panel. This is one dualie that actually goes off-road often.	Air Lift heavy-duty airbags...        read full caption Air Lift heavy-duty airbags help carry the load in back. The stock 3.73 gearing and factory limited-slip differential still live in the rearend.
There's no pretty show truck...        read full caption There's no pretty show truck here. Mount Logan's Chevy is really used, so excuse the dirt on the suspension. No clearance is lost with Tuff Country's IFS bracketry.	The Bully Dog downloader and...        read full caption The Bully Dog downloader and Performance Management Tool, or PMT, allows three performance settings to be quickly set on the fly and displays all kinds of useful information. It also looks cool.	The GM Duramax V8 diesel looks...        read full caption The GM Duramax V8 diesel looks deceptively stock under the hood.
...and works off-road without...        read full caption ...and works off-road without the trailer surprisingly well.	Mount Logan's Big Iron Chevy...        read full caption Mount Logan's Big Iron Chevy hauls this loaded 48-foot Motiv trailer with ease and works off-road without the trailer surprisingly well.	295/75R16LT BFGoodrich All-Terrain...        read full caption 295/75R16LT BFGoodrich All-Terrain T/AKO tires are on 16-inch KMC XD Series Rockstar alloy wheels. We like the black finish. The wheels really stand out when the tires get dirty.
The rear Rockstars look great...        read full caption The rear Rockstars look great in the dualie configuration. We were impressed with the BFGs' performance on this truck.	The Bully Dog downloader and...        read full caption The Bully Dog downloader and Performance Management Tool, or PMT, allows three performance settings to be quickly set on the fly and displays all kinds of useful information. It also looks cool.	A Lowrance iWay GPS nav unit...        read full caption A Lowrance iWay GPS nav unit keeps things on track, while the JVC DVD head unit keeps passengers entertained.
A long-range fuel tank was...        read full caption A long-range fuel tank was installed in the bed. John says he's going to cut it down about 6 inches so it doesn't interfere with the trailer.