Why doesn't GM give us HD trucks from the factory with solid front axles? Could you imagine how many more people would build and wheel them if it did? You don't have to be a Chevy guy to respect what GM Powertrain has been able to do with the General's drivetrains, but by off-road standards even Chevy guys scratch their heads over why the GM engineers dropped the ball in the front-axle department.
In order for Mitch Doukas (who is a Chevy guy) of Santa Cruz, California, to run the 39-inch Mickey Thompson tires he wanted on his '02 2500 HD, a Ford Dana 60 was slung under the Chevy by Central Coast Four Wheel Drive and sprung with Ford Super Duty leaf springs. The durability of this setup is proven and the looks speak for themselves. So until GM reverses its thinking on front axles (don't hold your breath) or we figure out a way to make the IFS hold up to huge tires (we're working on it, we swear!), don't expect to see many daily-driven HD trucks like Mitch's on the road. But if you do, try not to get too jealous.
We know most of you skipped right to this photo to find out how the high-pinion Dana 60 got under Mitch's HD. Central Coast Four Wheel Drive made the swap using Super Duty hangers and springs. The ride height was dialed in with a set of add-a-leaves, and the crossover steering uses the stock GM box with a drop pitman arm. It's a custom swap to be sure, but the simple design makes for a reliable and functional frontend. The cost (with labor) was about $12,000. At least Mitch hasn't had to ward off any of our ridiculous bulldozer attacks with his ORU diff covers. | 
As the stock IFS lay in the dumpster, new shock hoops that hang dual Pro-Comp ES300 shocks were fabbed up to dampen the motion of the 39-inch M/T Baja Belted tires. With 13 inches of suspension and a 3-inch body lift, the 18-inch-wide tires on Weld Racing wheels with 45/8-inch backspacing fit without any sheetmetal trimming. |
The rest of the 6.0L, 4L80E, and NVG263 drivetrain is still as stock as when it left the GM assembly line. Mitch kicks himself for not getting the 8.1L/Allison combo, but even he had to make compromises somewhere. For now, the performance mods are limited to 5.13 gears in the axles and Flowmaster mufflers. | |