Push or Pull?

It was pitch black as the empty Scenicruiser climbed an icy Colorado slope. Wheels spinning, it fought the grade, and the grade won. It slid sideways into a ditch. Oakie was driving, and never one to quit, he spotted a D8 Caterpillar parked in a field nearby.

As a “juvenile,” he had “practiced” driving a “borrowed” bulldozer, and he put that experience in play. Firing that jewel up, he strapped it to the Scenic with some chain and proceeded to jerk its butt out of the ditch.

Bad idea. Scenic parking brakes only use one axle (not enough on ice). The bus began sliding backwards, down the hill. It became a delicate balancing act, as Oakie drove the ’dozer fast enough to avoid being bashed, but not so fast that he put strain on the chain and made things worse.

Oakie had pulled, when pushing might have worked better.

There are two kinds of coaches, pushers and pullers, and it behooves us to choose wisely.

In vehicles, “pulling” (i.e., a front engine) is cheaper than pushing. Virtually all of these are body/chassis, with the engine and its accessories easy to find and maintain. Cooling is simple as radiators basking in the breeze. They’re less expensive to build and maintain.

Nothing comes free, and their “downsides” pushed them (pun intended) from the over-the-road market following WWII, but they are currently making a return.

Entrance doors eat useful floor space, and the front of their passenger compartment tends to be noisy.

Ride quality and handling aren’t as good. High-capacity pullers have a turning radius that rivals the Queen Mary, with the ability to sweep outside the turn with a swinging bootie. There’s the perception that if it has a “hood,” it might be a school bus.

Chassis builders only provide two axles, so weight is touchy when loaded. The lengthy driveshaft occupies space that a pusher uses for luggage. Body/chassis buses generally have a shorter lifespan (and lower residual value). Reduced acquisition cost makes them a good choice where mileage is low.

In a tougher duty cycle, the math becomes fuzzier. If they cost half as much but only have a quarter of the life expectancy…. (If I was good at math, would I be writing columns?)

Cleverly concealing the engine in back offers problems of its own. You have to stuff all sorts of delicate technology in a small, hot place where it’s harder to find and maintain. Cooling is tough. Heck, just checking the fluids is an adventure.

The passenger cabin is quieter because there’s more room for insulation, and baggage space abounds. Three axles make weight a lesser concern, and semi-monocoque construction can endure millions of miles. The public perceives them as more luxurious and safe because they sit above the “impact zone.”

Bob (appropriately known as Mace) was frustrated. His 4104’s battery was dead, and efforts to push-start it by nudging with an ancient Dodge van had been futile. A fan of inertia, he decided to back the van, and get a run at the ‘04.

Bob nailed the bussy butt at 20 mph and it did, in fact, roll off.  As a triumphant Mace leaped from the Dodge, its windshield fell out in the street. The steering wheel bracket had cracked, and from then on we would steer that sucker by pushing or pulling the wheel… no need to turn it.

In this case, pulling might have been a better choice than his aggravated version of pushing.

In choosing between front and rear engine, consider the strengths and weaknesses as they relate to your application. Don’t be Oakie… or Mace.

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