The Factory Trailer Hitch Was Replaced Because It Was Bending From The Strain Of Towing Off-Road.General Motors stopped building solid-axle four-wheel drive trucks in 1991 to pursue a better-riding and -driving pickup truck with independent front suspension (IFS). Fifteen years later, GM is the only OEM left building 3/4- and 1-ton IFS trucks. Imagine that. Thankfully, a few companies have developed retrofit kits to "right" GM's "wrong." At least, that's the way that Mauricio Natera of Sylmar, California, sees it. He knew he wanted a new four-wheel-drive Chevrolet Silverado 2500HD with Duramax power and the world class Allison 1000 automatic transmission. But, he didn't want any part of GM's IFS system with its CV-shafts, A-arms, and magnesium transfer case. Nope, Mauricio wasn't going to rely on any of that, so he figured why buy it, just to throw it all away?
That's why he started with an '05 two-wheel-drive truck. Since the frames are very similar between two- and four-wheel-drive GM HD trucks, he knew Off Road Unlimited's solid-axle swap kit would let him fit a set of leaf springs and a proven solid axle under the Chevy. To keep his truck all Chevy, Mauricio could have used a GM Dana 60 from a '77-'91 K30 pickup, but he had access to a '79 Ford Dana 60 that uses the more desirable high-pinion differential. Before sliding it under his pickup, Mauricio updated the Dana 60 with 4.56 gears, a Knoll Racing Power-Loc limited-slip diff, 35-spline stub shafts, and Spicer manual-locking hubs that Knoll Racing machined for use with the 35-spline stubs. To keep the factory antilock brake system functioning, the Ford 8-lug wheel hubs were turned, and Dynatrac tone rings were pressed on.
From there, Mauricio tracked down and rebuilt a divorced-style Ford NP 205 cast-iron transfer case with 32-spline front and rear output shafts and 1410-size yokes. The transfer case was hung on a custom crossmember that was built by Mauricio and welded up by Karl Knoll for optimum ground clearance.
Believe it or not, this truck began life as a two-wheel-drive. Mauricio Natera wasn't interested in driving a 4x4 with independent suspension, so he bought an '05 Chevrolet 2500HD two-wheel-drive Duramax truck and retrofitted a '79 Ford F-350 Dana 60 axle under the front. The Ford Dana 60 front axle is very desirable for this kind of conversion because it has a driver-side front differential, and unlike the '86-and-later Ford Dana 60s, the leaf spring perches are spaced closer together, allowing room for large tires. | 
The secret to mounting the 27-year-old front axle under the '05 Chevy was Off Road Unlimited's solid-axle swap kit. New leaf spring hangers, a trackbar, and shock hoops work with Atlas leaf springs to provide 7 inches of front lift. An ORU sway bar kit was added to tame the front suspension, and an ORU hydraulic ram-assist steering kit was fitted to turn the wide 37x13.50R17 Pro Comp X-terrains mounted on Weld Racing Cheyenne 8 wheels. |  |