The components of modern vehicles include numerous servomotors – e.g. for electric parking brakes, power windows, sunroofs or windscreen wipers.
One such servomotor has been subject to complaints because the noise inside the vehicle was too loud and was irritating to passengers.
It isn’t possible to make changes to the design during the current series without investing considerable time and money, because the corresponding validation processes are too long and expensive. It is relatively easy, however, to achieve significant improvements quickly and cheaply by changing the lubricant.