Why are steering wheels on busses and large trucks more horizontal than those in small trucks and cars? It seems like you have to bend over more to steer in that configuration, which would be tiring… wouldn’t it?
Part of it is probably because the steering column needs to be at that angle because of the design of the vehicle. Granted, another U-joint would alleviate that, but that would add cost and these vehicles are designed for minimized cost and weight.
A more important reason is leverage. More force can be exerted on the wheel with the push/pull motion than can be with the wheel in a more vertical position. Before power-assist steering became common one of these monsters may have been nearly impossible to control with a more vertical wheel.
Hmmm… could be something to the angle argument, but minimum weight sounds farfetched.
Okay, why do they continue to do this even after the introduction of automatic transmissions and power steering?
Just a WAG: Could the diameter of the steering wheel have something to do with it? The bigger the vehicle, it seems, the bigger the steering wheel. If the steering wheel of an 18-wheeler were vertical, the driver’s legs would be in the way.
*Originally posted by jdnewmil *
I’ve heard that they have larger wheels so the driver can get more leverage, too. My guess as to the reason they have this with power steering is probably convention (they give them big wheels because they’ve always been that way) and maybe driver familiarity (they’ve always driven trucks/busses with this arrangement, it feels more natural to them that way).
I believe Mr. Blue Sky is correct.
Now I keep hearing “Sweet Talkin’ Woman” playing, and I can’t get it out of my head…
I would have loved such steering wheels back when I was in the Army! The old 2.5T trucks didn’t have power steering. When the ground guide (the person helping you back up) was an idiot, we had to turn the wheel all the way back and forth to park the truck and its trailer straight. Horizontal mounting of the steering wheel would have been great.
Less than 3 years ago I regularly drove a truck with no power steering :(, big horizontal wheel definitely helped. The truck I drive now has a smaller wheel (but still bigger than in a car) that tilts down to about a 45[sup]o[/sup] angle :).
The horizontal steering wheel may help with fatigue on long highway drives since you can rest your hands flat on top of it and much lower than your shoulders compared to keeping your hands near the top of a vertical wheel.