Why do busses, trucks have a nearly horizontal steering wheel compared to regular cars?
In: 673
[removed]
Easier for finer control, and because since many busses have flat noses, the steering rack is way more at a near horizontal angle.
because the steering gearbox is underneath the driver almost vs below from in front of the driver. This is done on larger vehicles to shave inches off the overall length of the vehicle for maneuverability, and on old trucks and busses,overall length was restricted by law,which gave rise to cab over trucks,because making the cab shorter was more profitable than making the trailer shorter and hauling less. Now there is only a restriction on trailer length,but still inches may make the difference in getting in and or out of a place,so inches are still shaved in many ways.
This is mostly on buses and short nose trucks. In long nose trucks, the steering is fully adjustable, like in a car, but still has a fairly large wheel in case the engine stalls and you find yourself out of gear and can’t get back in. The angle depends on how much room you have & where the steering gears are located. The size of the wheel is so you can get extra leverage to turn without power steering and the even larger wheels are for those without power steering at all.
Source: Got a company truck that liked to stall and was without power steering a few times.
Space in a bus or truck is for producing revenue, the operator is given as little space as is safe. I drove truck for 30+ years. The more upright position of the steering wheel takes up less length in the vehicle. The auto transport trucks I drove had the engine compartment partly inside the cab, we had the roofs cut down by 8 inches so a car would fit on top to not be too tall, and hang out the front past the front bumper, we did not have sleeper cabs as that would take up the space to haul one more car. The last rigs I drove could haul up to 12 cars. and were 75 feet long when empty and all the extendable ramps were pulled in.
Most trucks and cars hove power steering. However, it’s useful to have a backup.
In your car, this isn’t an issue. But in a truck/bus, you’ll need leverage, especially if turning while stationary. A vertical wheel would require pushing yourself either into the air or into your seat. A horizontal wheel, however, can push your back into the seat, or pull against your legs.
Bus driver here.
Large vehicles like buses and trucks have very large steering wheels relative to most passenger vehicles, so you can exert finer control, and have more torque to turn the wheels (larger circumference, more power/easier to turn). The latter is not as crucial given that most large vehicles today use power assisted steering, but in an situation where the power steering failed- an extremely rare occurrence, you would need to revert to “armstrong” steering (yanking it around with brute force).
If you look carefully, though, you’ll find that the large, flat-oriented steering wheel is more common on “cab-over” designs, such as flat-fronted semi trailers and the transit-style flat-front buses (known as Type D buses). That’s because the steering wheels are beneath or even well behind the driver, requiring the steering shaft to be more vertically oriented relative to the driver, which necessitates the use of a flatter steering wheel, which also means it needs to be larger to operate it properly.
When you look at what are typically called “conventional” buses and trucks- with buses they’re the Type C- which have the engine in front of the driver under a large nose, along with the steering wheels under the engine, you’ll find that while the steering wheel is frequently somewhat larger than in a passenger vehicle, it’s more vertically-oriented and not nearly as large as the cab-over designs, because the angle of the steering shaft is different.
**Edit:** There seems to be a thankfully, very few people, who’ve taken issue with my explanation, specifically that I first talked about the *size* of the steering wheel instead of going directly to the orientation. But in my mind this is *explain* like I’m five, not *answer* like I’m five, and in order to properly explain, it’s necessary to start with the size because- as I go on to explain, not all trucks/buses have the oversized steering wheels, depending mostly on the orientation of the steering shaft to the wheels.
With the larger diameter steering wheel it has to be up out of the way of the drivers lap.
Put a 3ft steering wheel on your car and you won’t be able to steer because the steering wheel will be on your lap.
Simply put: the steering column is pointing as close as possible to the front (steering) axle. The wheel is perpendicular to the column.
For a bus, the driver is very close to, over, or even in front of the front axle.
No one in the top comments have mentioned that it is easier to crank a wheel numerous rotations that is horizontal rather than near vertical. The number of rotations needed for some maneuvers in buses, semis and tractors can get ridiculous and the ergonomics would be exhausting
Source: I have a big old tractor and the steering box placement has nothing to do with steering wheel angle
Latest Answers