World’s Largest Mack Truck Is Getting a New Shot at Life After 55 Years

For every perfectly preserved, eight-figure collector car that surfaces at Amelia Island or Monterey, there's a vehicular treasure that's stashed away for good, never to be seen or enjoyed by the public again. While it's clearly different from a pre-war Bugatti, my mind goes to Ford's experimental turbine semi-truck named «Big Red,» which was hidden for years until my old coworker Peter located it. Something in that same vein is happening in New Jersey right now as the last surviving Mack M100SX, the largest truck ever built by the manufacturer, is being restored after decades of disuse.

Normal tractors have nothing on the M100SX. It's so gargantuan and so specialized that Mack built just three of them in the mid- to late-1960s; this one was completed in April or May 1967. It measures 32 feet, 1 inch from the front bumper to the back of the frame. From the ground to the top of the cab, it's 13 feet, 6 inches. And the weight? Even without the body, it clocks 95,485 pounds according to the original literature. The GVWR is massive at 331,875 pounds, meaning its payload capacity exceeds 100 tons.

The original engine is a two-stroke Detroit Diesel 12V149T, which translates to twelve cylinders arranged in a V at 149 cubic inches each. My rural public school education helps me calculate the total displacement at 1,788 cubic inches, or 29.3 liters (OK, I had to Google the conversion on that). It's twin-turbocharged to 1,000 horsepower and makes 2,500 lb-ft of torque at 1,900 rpm. I can only imagine the size of those pistons since every cylinder has more displacement than an entire Honda Civic engine—and there are 12 of 'em.

A post shared by Eddie Congdon (@eddiecongdon_trucking)

I first heard rumblings of the behemoth's resurrection on Facebook, where retired truckers reminisced about spying on the truck in a past life. Several noted it had been moved from its longtime resting place, the Pile Foundation Construction lot in Far Rockaway, New York, on Long Island. Some searching around the web turned up a video of the Mack being transported in pieces by Dave's Heavy Towing out of Hillsborough, New Jersey, and the sight was spectacular.

As it turns out, the Mack was on