ZF AFTERMARKET SWITCHABLE ENGINE MOUNTS
Made for greater ride comfort
Under its LEMFÖRDER brand, ZF Aftermarket now offers switchable engine mounts as OE-quality spare parts.
These intelligent components are mainly used in luxury vehicles, where they ensure the lowest possible vibration and noise both in idling mode and in operation due to their switchable characteristic curve.
Engine mounts function as the connecting element between the engine or the transmission and the vehicle body. It is not possible to use a simple solid screw connection as it can transmit vibrations, noises and movement from the drivetrain to the vehicle.
That is why automobile manufacturers use rubber-metal parts, or hydraulically dampened engine mounts to improve ride comfort. Yet even this approach cannot offer ideal vibration damping under all conditions, says ZF Aftermarket.
In order to counteract this, switchable engine mounts were developed so that one component would meet the demand for both a high level of comfort in idling mode and driving dynamics.
An integrated air spring offers a possible variant here. If the engine is in idling mode, an air spring in the engine mount is activated via a switch. This air spring absorbs the low-frequency engine movements while the vehicle is at a standstill. During driving operation, the mount switches over to a hydraulic mechanism depending on vehicle speed and rotational speed. Doing so makes the mount considerably harder, simultaneously creating greater freedom of movement for the connected components.
ZF says it has developed electronically switchable engine mounts which can actuate two different characteristic curves depending on vehicle speed and rotational speed.
Noises and vibrations can signify damage
Engine mounts are prone to wear, which can be difficult to diagnose as they are usually installed under cover and hidden behind cladding. Fluid leaks or signs of rubber deterioration; stronger vibration transmission to the vehicle body; noticeable engine movements (reverberation) when switching off the engine and clicking noises during load changes are just a few problems which could indicate a defect.
ZF Aftermarket recommends workshops use OE-quality spare parts with exactly the same design as the OE part originally installed as even if the engine mount model fits into a different engine geometrically, like a gasoline engine instead of a diesel, there could be major differences in the engine mount design. It also recommends all engine mounts be replaced during repairs, not just the defective part.
ZF Aftermarket offers LEMFÖRDER switchable engine mounts for several Audi and Mercedes-Benz vehicle models.
For further information, contact ZF Services Australia on 1800 ZF SALES (1800 93 72537) or visit www.zf.com/au