Forget feeble 4x4s. The 6x6 seems to be the new monster truck that everybody wants. While we can't imagine why anyone would practically need one of these beasts unless you're trying to scare other road users, we've already seen the $400,000 Ford Bronco 6x6 and an equally preposterous Jeep Gladiator 6x6, both revealed earlier this year.

The latest vehicle to undergo a 6x6 transformation is a 2013 Chevrolet Silverado 3500 HD. Hardly a small or inconspicuous truck in standard form, this particular 3500 HD is a custom pickup listed on Mecum Auctions. It has rather appropriately been named 'Yeti'.

Yeti was built by Hobbs Automotive, Inc. and the company seems to have gone all out to create this imposing Chevy. The basis of it is an M939 A1 tractor five-ton military 6x6 chassis. M939 military trucks are used by the US armed forces for a variety of roles and are manufactured by AM General. With its five-ton Rockwell axles and enormous tires, the body of the Chevy almost looks dainty on top of the serious hardware lower down. It's not just any 3500 HD body, though. The bed had to be stretched to a lengthy ten feet to make room for the bigger chassis, which should make this quite the cargo hauler. You'd probably need a ladder to reach the bed, though.

No curb weight has been mentioned but this has got to be a seriously heavy beast. To make sure it can actually move at any decent pace, it's equipped with a Cummins 855 CI diesel engine. This 14-liter powerplant produces 240 horsepower and 685 lb-ft of torque, which doesn't seem all that much for such a massive vehicle. It's paired with an Allison five-speed automatic gearbox. The Yeti also comes with a Rockwell two-speed transfer case, a Kenwood sound system, and a custom camera system - no amount of cameras are likely to help you squeeze into an average-sized parking bay with this thing, though. The mighty truck will go up for auction next month in Orlando.