We had a 2007 Chrysler (with only 88,000 miles!) in last week with failing motor mounts. The amount of movement that occurred between the engine and the engine compartment (without the engine falling out of the car – thankfully!) was amazing. Take a look at the video, and you will see the significant shift of the engine.
Video: Engine Mounts Failing
This client had been hearing noises under the hood for some time, especially upon acceleration. When we saw the obvious movement, we knew that was where the noises were coming from. We changed the three motor mounts and resolved her concerns.
So what is a motor mount and what is its purpose? Motor mounts hold the engine in its proper position, especially during stops, starts, turns, and over rocky/bumpy terrain. The rubber insulator also reduces vibration and noise, cushioning the engine in the compartment. If one mount loses its stability, your engine can drop on one side or become misaligned and will place stress on the other motor mounts.
Obvious noises (like a “thud” or a “clunk”) especially when accelerating, shifting gears or putting the car into reverse, are indicators of the motor mounts going bad. Often, people think their transmission may be the problem. Keep in mind that the motor mounts generally do not go bad or fail suddenly. However, when they do fail (like in the video), the engine will be very unstable. This customer was lucky. Typically, when motor mounts get this bad, they will often affect other critical components (like your radiator, hoses, belts, and transmission linkages) and cause more extensive problems.
Since you are the one who drives your car the most, you are the expert on what noises are normal and when your car noises change. Certainly, if they change slowly, they will be harder to detect. Being aware of increased vibrations when the engine is idling, or if you hear or feel “clunks” when starting and stopping or going from park into reverse, be sure and bring those noises to our mechanic’s attention. We like to drive your car with you to hear and feel the exact noise you have noticed.
Just like many of the components that make up your car, time and miles will take their toll. Think about all the stops, starts, and turns you make every day! Each of those movements create stress on the motor mounts. The way you drive does make a difference…avoid “jack rabbit” starts and speeding up to a stoplight and then slamming on the brakes! All of these sudden movements significantly increase the stress on the motor mounts.
The rubber cushioning portion of the mount can also become brittle and eventually crack (dry rot). Our dry climate further contributes to the loss of elasticity in the rubber insulator. Also, leaking engine fluids (oil, transmission or power steering fluid) onto the motor mount can accelerate deterioration of the rubber portion, thereby losing critical support needed for engine stability.
Consistent maintenance and attention to details on your car can save you money in the long run, by avoiding expensive repairs and catching small problems before they become BIG problems. Let us help you keep your car running reliably and safely for as long, and for as many miles, as you choose to drive your vehicle.