Dozens of major and minor modifications went into the building of Glyn Lewis's "heavy Chevy" pickup built out of a 5-ton truck.
"It took years to get it the way I wanted it," says Lewis, who runs a Caledon, Ont., dragline service. "I don't think I'd ever attempt such an ambitious project again. It was interesting and often frustrating, too."
Lewis mounted the body of his 1966 GMC 1/2-ton pickup on the frame of a 5-ton Chevy C-65 truck. He installed a rebuilt 4-71 Detroit diesel engine, which had 200,000 miles on it, using hockey pucks for motor mounts.
"It rolls along nicely at 55 mph at about 1,500 rpm's," Lewis says. "It has the capability of going 92 mph, but I'm not interested in collecting speeding tickets. I've had it up to 75 mph a couple of times myself so I have no doubt it'll do 92 mph."
Not bad for a 1/2-ton truck boasting a 1-ton engine under its hood.
Installing the engine required major rebuilding of truck frame and body.
The C-65 truck frame was fitted with a new crossmember to support the engine. "I positioned the new frame right behind the truck, then slid the cab, home-built box and fenders back onto it and bolted them down," he says.
After a hole was cut in the firewall to accomodate the engine's big bellhousing, the diesel was bolted in place. (Six layers of carpet over the firewall and strips of thick rubber conveyor belt for floor mats helps keep the cab quiet, Lewis says.)
The engine is coupled to a Clark automotive-size 280-V 5-speed transmission with 5th gear overdrive. The engine fly-wheel was retapped for a 13-in. dia. single plate clutch, instead of the truck's original industrial-size clutch.
Completing the drivetrain is a Dana 60 3/4-ton rear axle with faster, 3:73 ratio. It's driven by a custom-built driveshaft.
The truck's front axle is fitted with 8.25 by 20-in. tires. To mount the same size tires on,the rear, Lewis had to have 20-in. rims built for the rear axle. He had 9/16-in. plate welded in the center of the rims and stud holes bored.
The big tires and brake drums and shoes off the C-65 required a dual master brake cylinder instead of a single bore cylinder. "Step on the brakes too hard and you'll go right out through the windshield over the hood," he notes.
The 2-way hood can be opened front to back like a conventional pickup or flipped up from in front of the windshield. The double-hung hood was necessary to provide easy access to the big engine without changing the looks of the pickup body. The hood and fenders flip forward on a hinge made of pipe fitted about 2 in. above the frame rails.
The two-way design hood required mounting the special-made radiator (with water outlet on the bottom facing front) on a separate frame. That way, the radiator stays in place when the hood flips forward.
The box and fenders were custom-built along with the exhaust system. Lewis made a muffler out of an air brake tank off an old semi. Baffles were welded inside and the muffler was mounted under the cab. Pipe and square tubing direct exhaust fumes out store-bought 3 1/2-in. dia. chrome twin stacks, one on each side of the cab.
A power steering unit from an old IHC truck replaces the original manual steering. The power steering unit mounts in a special bracket on front of the engine.
The pickup's dashboard was retrofitted with Stewart and Warner gauges.
Lewis says the pickup gets 22 to 24 mpg, even though it weighs 7,400 lbs. "If anyone's planning a repower job like this, you can probably figure it'll end up costing three times what you expected," he says. "Between this project and the original repower -- I installed a 3-71 Detroit Diesel in the truck first but was unhappy with the results -- I've spent well over what a new pickup would have cost, but I've got one of the most unique vehicles on the road."