You know how heavy your engine and transmission are, so you can imagine how tough the parts that hold them onto your vehicle’s sub-frame must be. Not only must they support the weight, they also have to isolate vibrations and noise from the passenger cabin. Pretty tall order, wouldn’t you say?
The parts that face that task daily are called the motor mounts, or engine mounts. They are usually made of rubber with steel brackets. Others contain a liquid for vibration and sound isolation.
Most vehicles have three or four motor mounts, and while rubber or hydraulic liquids do a good job of damping the vibrations from the engine, they also have their limitations. The problem with rubber is that it gets old and brittle. Plus, if there’s an oil leak anywhere in your engine and oil gets on the rubber motor mounts, rubber will deteriorate even more quickly. As for the liquid motor mounts, they can develop leaks and stop working.
Here are signs a motor mount is going bad. You may hear a loud clunking or banging sound under the hood. That means the weight of the engine is shifting around enough to bang against other metal parts. You may feel bad vibrations, and the engine may feel like it’s moving around in a strange way.
When things get to that point, your vehicle can be damaged from that heavy engine knocking against things, and its time to replace one or more motor mounts. Schedule a visit to your vehicle service facility. There, a technician will assess your motor mounts; if one bad one is found, it’s not unusual that others are likely to fail soon and should be replaced before they do.
Because all vehicles are configured differently, some motor mounts are easily replaced. But others can be much trickier, take a lot longer and therefore are more expensive to replace.
It’s important for your engine’s health to make sure motor mounts are sound and solid. You will maintain that quiet, vibration-free ride and could save your engine and transmission from major wear and tear.