One of the biggest mysteries that came out of my time at “the yard” involved a late 1970s GMC truck. The squarebody was as they usually were in the later 1990s at the time in the Pacific Northwest, nice and used but still solid and useable. It had a nice small lift, was built like a brick house, and on first drive had enough torque to drag around the trailer house if we hooked up a big enough chain. But the exhaust note was freaking weird. Sure, if you dropped the hammer on a dirt road you wound up digging two perfectly straight ditches, but after a quick investigation showed only six spark plug wires, the call was made that the GMC had to be stripped. Frankly, out of many regrets that came from that yard, that GMC was one of the biggest…I should’ve made a play for it as my first ride but back then I didn’t know what a GMC V6 was. Nobody told me that they were workhorses that could be put through damn near anything. Nobody told me that I could run a 2.71 gear out back and I’d still pull like a freight train. I was just told that it was a six-cylinder truck and therefore, it was worthless.
If you don’t understand what I’m carrying on about, hit play below. And when you do, pay close attention to the speedometer as this guy gives the 478 cubic inch V6 (yes, that is correct) the business end of his right foot. Barely work the engine and it pulls along dutifully, maybe not at alarming speed but competently. Bury the pedal and you’ll see why I would love a time machine right about now…
My Dad had a trucking company up till the early 70’s using GMC’s. They all had 478M (magnum) engines. One had to be careful if you got stuck. If the tires wouldn’t turn they snapped axles with ease.
Worked for our township in the late ’60s early ’70s on the GMC COE garbage trucks….great summer job. Walked past one of these freshly removed for rebuild, it was enormous. While strapped to a pallet stripped to a long block it was up to my waist and I’m 6′. The mechanic said it was close to 1000lbs.
Nice. What two speed axle are you using?