Vibration, buzzing and knocking under the floor – these are the signs that the drive shaft in our car may have been damaged. We can choose between complete replacement of this element or its regeneration. On which option it is worth to decide?
Replacement of the drive shaft or its regeneration? The first solution means longer life of the element, the second is obviously more economical. One thing is certain: there is no need to delay with the repair, because driving with a damaged shaft can quickly lead to further defects and related expenses.
Drive shaft and its task
The job of the driveshaft in a car is to transfer torque from the engine to the wheels. The component connects the gearbox to the drive axle and is most often used in cars equipped with rear-wheel drive or in 4×4 cars. It is a tube made of steel or aluminum, which in simpler systems consists of a single part, and in more complex systems of several elements connected by bearings. The most popular designs include shafts with universal joints (so-called cardan shafts), as well as with metal-rubber joints and constant velocity joints
Beware of shaft damage
The drive shaft is an operating part of the car, which is exposed to high overloads during driving. Its wear is primarily affected by the number of kilometers driven and the operating conditions, especially driving on bumpy and uneven road surfaces. The driveshaft also wears out under hard starting and braking. Neglected maintenance is also a cause of defects – the component often fails as a result of insufficient lubrication or heavy contamination. Its proper operation should include regular control of clearance (once every 1-2 years)
Symptoms of defects
Malfunctions of the drive shaft are usually difficult to detect during inspections at the diagnostic station. However, it is easy to recognise the symptoms while driving. Vibrations, vibrations and buzzing coming from under the car are the most disturbing signals. Our attention should also be drawn to loud rattling in the joints – especially noticeable when accelerating or braking, as well as rumbling when starting from a standstill. Confirm your suspicions will be an external inspection – on the joints of the shaft should then feel the clear play.
Do not delay with the repair
Appearance of any of these symptoms is a signal that we should as soon as possible visit the garage. Delaying the repair can lead to more serious damage. Vibrations of the shaft can cause loosening of the connections of other parts of the car, such as in the braking system. Damage to the driveshaft can include wear and tear on the bushings, universal joints, and support bearings. Fortunately, most of this damage does not mean that we have to replace the entire shaft for a new one. The repair will most often consist in regeneration of the damaged elements, which is associated with much lower expenses than in the case of buying a completely new shaft.
What is a driveshaft reconditioning? The first step is disassembly of all the elements of the system and their thorough cleaning by sandblasting or shot blasting. Then individual elements are subjected to thorough diagnostics. Defective parts – joints, seals, supports, half-shafts and crossmembers – are replaced with new ones. The next stage consists in applying special preparations to the shaft, which are supposed to prolong the life of the whole system. Regeneration of the shaft consists also in its balancing, thanks to which it gains the proper geometry. This is to prevent vibrations and, consequently, subsequent failures. Finally, the shaft is applied a layer of protective varnish, which protects the element from corrosion. Remember to perform the regeneration of the shaft in a specialized workshop in this direction.
When to replace?
Significant damage to many elements of the driveshaft may mean that their regeneration does not make sense. It is also worth remembering that the life of the remanufactured shaft will be much shorter than in the case of a completely new element. The cost of buying a new set is an expense of 300-500 PLN. In this way we gain a manufacturer’s warranty and confidence that it will serve well for a long time.