Last month we laid out a plan to build up an Ultimate Adventure truck out of a 30-year-old beater as kind of a break from our norm of turning a late-model truck into a turnkey wheeler. But we thought building an everyman 4x4 like this '75 1/2-ton seemed cool because people actually wheel these things. We knew we had a wish list of parts we wanted to run and a few crazy things we wanted to try, but the first order of business was to find a shop insane enough to help us with the project. The techs at GM Truck Center in Burbank, California, are pros when it comes to solid-axle GM trucks and are experts on everything from lift kits to complete truck restorations. In no time our UAK10 was stripped down to cab and frame and sent out for a steam cleaning, while we hung out at the beach ... er, rounded up some parts back at our office. This month we show you how we cheated with a no-adapter-required engine swap, and prepped our Chevy truck for a Ford-style front Dana 60. In the next installment, we'll show you our brutally simple suspension plan and whatever else we can sneak in under our deadline.
Solid-axle Chevys are notorious for having frame problems around the steering box. GM Truck Center has fixed a hundred of them but as luck would have it, our '75 was one of the worst they've ever seen. John Hughbanks ground out the cracks and pieced the frame back together with a Hobart Ironman 250 MIG. To keep it from cracking again, Hughbanks added a reinforcement plate ($70) from J.C. Whitney and then bolted in an Off Road Design steering-box brace ($120) to keep everything in place.
Try not to puke on the screen ... but we're going to put a Ford transfer case in our Ultimate K10. We'll get to the "how" in a minute, but we'll start with the "why." First we tried to use an NV271 case from a Super Duty because it's got a great low range (2.72:1), fixed flanges on both outputs (32-spline front/34-spline rear), and a 7,890 lb-ft input torque capacity. Unfortunately they're also too wide to fit in the frame of our K10! So we went with the time-tested Ford NP205.
Why not the GM NP205? Well, the Ford version is more common than the GM. And all Ford 205s have the big 32-spline output shafts front and rear. Plus if you're like us and want to use your 205 behind an Off Road Design Doubler you need the big bearing input gear that the majority of Ford 205s have. Which bring us to the "how." By the nature of the $785 ORD Gen II Doubler ("Doubler Low-Low Range Transfer Case," July '05), your NP203 range can be adapted to work with a Dodge, GM, or Ford NP205 - which is perfect for us 'cause we want to run a '78-'79 Ford high-pinion Dana 60 (driver-side differential) front axle.