The Quest for Peace and Quiet
Driveline vibration can be felt in the cab and it can result from incorrect driveline angles, damaged U-joints or an unbalanced condition.
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Driveline vibration can be felt in the cab and it can result from incorrect driveline angles, damaged U-joints or an unbalanced condition.
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Noise, Vibration & Harshness is not the name of a truck-chasing law firm. NVH is something manufacturers try very hard to engineer out of their products, but it’s often like a game of whack-a-mole. Once you solve one problem, another shows up.
Take the effort to reduce noise levels inside the cab. Engineers do everything possible to eliminate the obvious sources of noise and vibration – they design new cab and engine mounts, they isolate the frame and the powertrain from the cab as much as they can. Then, with the newly quieted cab, drivers start noticing the squeaks and rattles they were couldn’t hear before because of engine and wind noise.
Consider the possible sources of NVH: engines, tires, suspensions, cab squeaks, wind noise, drivetrain, brakes and more. Truck and engine makers and component suppliers test endlessly for NVH, seeking to isolate the source of the noise or vibration from the cab if they can’t reduce or eliminate it at the source.
Some sources of NVH are third-party sources. Tires, for instance. More aggressive tread patterns, such as lug or open-shoulder tread, tend to be noisier than rib-tread tires. The tire noise doesn’t make its way into the cab through physical contact with the cab, but by being a source of noise that happens to be in close proximity to the driver.
Tires and wheels can also be a source of vibration, such as when they are unbalanced.
“Drivers feel the vibration either through the steering column and steering wheel, in the case of a steer tire problem, or through the cab floor and seat in the case of a drive tire problem,” says Steve Ludwig, senior product development engineer at IMI, …Read the rest of this story
