left engine motor mount.

Engine mounts do not have a life expectancy. But as anything ages, it becomes susceptible to failure due to age and wear and tear. Most notable is that engine mounts feature rubber dampeners as major parts of them, and they dry rot as they age. When this happens, they can tear due to normal aging and weakening. Additionally, if oil happens to leak on them, the rubber can deteriorate even quicker. There is a top "strut" style engine mount, a front mount, a rear mount, and a transmission mount on your Acadia.