Motor mounts stay your engine firmly attached to the chassis in the engine bay so that it doesn't shift while you make turns; go up or down hills, or over uneven terrain. Since motor mounts are continually under stress, it's not astonishing for them to go bad in a high-mileage car. Several models may seem to be more at risk to bad motor mounts, but it can occur to any car if you own it long enough or drive it over the rough floor.
Engine or motor mounts are made in a variety of shapes and sizes to fit a wide variety of needs, but they all serve the same purpose of mounting the engine and dampening engine vibration. They are usually made of metal and rubber. Metal withstands the force and torque generated by the engine, and rubber absorbs and dampens vibrations. As engines make a substantial amount of vibration in their normal process, when there is a trouble with the motor mounts, increased feelings can usually be rather noticeable.
Signs You Need to Replace Motor Mounts:
Engine mounts, as the name might propose, are designed to firmly keep an engine input. One of the first tell-tale signs that it may be time to replace one is if you're experiencing excessive vibration. While your car may make some noises that sound as though something's vibrating, this type of vibration is actually felt, instead. The vibration dampening effect of the engine mount may be diminished, which will transmit the vibration and noise from the engine, through the chassis and into the cabin.
Your car's engine is a finely tuned, intricate piece of machinery. As such, one of the key roles of engine mounts is to keep the engine is properly aligned/positioned. This is to ensure that the height is equal on all sides. A sure-fire indicator that you might be in the market for a new engine mount is if you notice your engine drooping to one side. This is a simple visual check under the hood, and could save you a lot of time, money, and heartache, should your engine's tilting become excessive enough to cause real damage.
Broken Belts and Hoses:
Bad engine mounts can too lead to injured fan belts and/or radiator hoses. While this typically occurs at high speeds, it's important to check your belts and hoses for any damage.
The most common symptom of bad/failing engine mounts presents as a lot of noise coming from your engine. Keep an ear out for any strange sounds, like knocking or clanking, as this is a pretty clear indicator that something is wrong. Not every noise is directly related to your engine mount, but it is almost certainly related to some kind of problem that requires attention.