Why Drive Shaft Noise Is a Safety Problem Not an Annoyance

A clunk on take-up or a hum that rises with speed is the driveline telling you something has worn. Here is how those noises map to the joints, the centre bearing and the balance of the shaft.

In theory, the drive shaft of a front-rear-drive or four-wheel-drive vehicle is the core component of the drivetrain, its connected transmission or transfer box and the rear axle differential; Power is transmitted in a "rotational" way, as long as the vehicle is moving, the drive shaft will turn at a high speed. Power is output from the engine and amplified through the transmission, which then acts on the drive shaft, that is, the drive shaft is always subject to torque; In popular terms, it will be twisted by a force, if the drive shaft itself material or structural strength is not strong enough, it may be twisted, of course, this situation basically will not happen.

The specific problem to the car is not on the drive shaft, but the flange connecting the drive shaft has a design error, and there will be abnormal sound after long-term high load operation; And the sound is caused by the vibration of the object, so the location of the transmission shaft flange must be vibration to bring abnormal sound, the transmission shaft abnormal vibration how can there be no hidden danger of driving?

Why Drive Shaft Noise Is a Safety Problem Not an Annoyance — supporting photograph

What is a flange?

Flange, also called flange, also called a flange joint, which is a kind of connector that looks like a plate, is used for connecting the shaft to the shaft; Or understood as the connection between two pipe ends, many flanges will be used on the car, and it is also common when modifying the vehicle. For example, remove the wheel and add a 20mm thick flange, fix the flange on the half shaft first, and then fix the wheel on the flange, so that the wheel base can be increased by 40mm (symmetrical installation flange).

Some modified vehicles are off-road or racing after the installation of flanges, and there will be serious accidents in the process of wheel falling off; The reason is that the material or structural strength of the flange does not meet the standard, and the flange is directly twisted off during high load operation.

If the transmission shaft flange of the car is in line with the vehicle power transmission system standard, there should not be abnormal vibration in theory; On the contrary, once there is abnormal vibration, it means that the fixed flange and the parts themselves have been abnormal, if the owner's driving habits are intense, the drive shaft flange will be in a high strength or super strength state for a long time, and the fracture is not impossible.