If there was a competition for “bus slalom,” my buddy’s weary old 4106 could have contended for the gold.
He’d checked everything: tie rods, bearings, tires — even the steering box — to no avail. That jewel cruised Interstate 95 zigzagging like a WWII convoy avoiding U-boats.
Since recent columns taking on left- and right-hand turns didn’t result in any nasty repercussions, it seems safe to take a shot at “driving straight.” It shouldn’t take a ton of skill to navigate a highway, but there are factors that can make it challenging.
In the case of the meandering GM, after going through everything connecting the steering wheel to the tires multiple times, my pal found a sneaky little gear hiding in a bulkhead that was worn. Any time your bus seems to have a mind of its own you’ll want to check all the mechanical stuff and tires for wear.
When it comes to front tires, you should not play favorites. They should each get the same amount of love (and air).
There are other technical factors that can cause wandering and excessive tire wear. Improperly adjusted toe-in, caster and camber can all make a difference in how willingly a coach goes where you point it.
In ye olden days toe-in was the one you could adjust (you wanted your bus to be slightly pigeon-toed). Some modern buses with independent suspensions allow you to set caster, which is an angle on the steer axle that makes your tires want to come back to center.
If any of these are out of “spec” you’ll get poor tire wear at a minimum and squirrelly handling at worst. Unlike me, a smart person can often look at tire wear patterns and know what’s not right.
Assuming all your mechanicals are up to snuff, there are a variety of other factors you can use as an excuse for weaving. Crosswinds can create problems. It’s fairly obvious that they push on the side of your coach, but how hard they shove varies with the bus.
The length of the coach, as well as its height, determine how much “sail area” you have to contend with, but other factors like wheelbase and number of axles are considerations.
Wind can be cunning, too.
We once had a Scenicruiser blown off the road by a gust that sneaked in between two hills. That jewel lay on its side like a giant French fry. When we got a closer look, it had been transformed into a crinkle cut — totaled.
Coming out of a tunnel can be exciting because wind conditions at the exit are often different than the entrance, perhaps because there is usually a mountain between them.
Lest you think you’re safe in an urban environment, under some conditions tall buildings create their own microclimate. Driving atop a raised highway gives crosswinds an extra shot at you.
You can be passing a truck (or, heaven forbid, vice versa) and when you ease out of its shelter, be blown sideways. In addition, large vehicles all trail at least some turbulence that can misdirect you.
The recent revival of shorter coaches makes things even more interesting. Many are the same height as their 45-foot siblings, but have a shorter wheelbase and no tag axle acting like a rudder. I’m not smart enough to know how much, but they certainly behave differently in a gale.
Roads are crowned to encourage rainwater to head towards the shoulders. Your bus will often follow that same sideways path unless you give it direction. This is one reason why so many nighttime accidents involve vehicles straying off the highway at a shallow angle, while the driver snoozes.
The good news is that there are a couple of things you can do that will keep you on the “straight and narrow.”
First, slowing down negates virtually all these spoilers. Crosswinds don’t move you as far, and turbulence is lessened when you’re driving slower.
Second, paying attention gives you a chance to anticipate a truck’s wake, or a wind-gust sneaking between buildings or hills. Staying wide-awake prevents the road’s crown from taking you down.
And third, have a feel for the coach you’re driving. How does it react to road conditions? Is it different than other buses you’ve driven?
My pal Oakie used to check alignment by driving a 4104 slowly down a straight stretch of road. He would leap out of the drivers seat, run to the back of the bus and touch the lavatory door, and scurry back behind the wheel. If the coach hadn’t left the road, alignment was adequate.
It wasn’t QUITE as scary as it sounds, since a 4104 was only 35 feet long.
Which brings us to the most significant factor in safe bus navigation. Never allow a loose nut behind the wheel.
Dave Millhouser is a bus-industry marketing consultant and freelance writer. Contact him by email at Davemillhouser@gmail.com.