Bad Engine Mount...
2003 Nissan Maxima 4dr Sdn GXE Auto Repair Service Manual Specifications 03
Could broken engine mounts cause shaking and shuddering between 60 and 70 miles per hour?

My car shakes and shudders on the freeway starting at around 60 mph, and ending around 70 mph. It started out gradually, a few weeks ago, but got worse very rapidly. When I ran a search on that symptom on car related websites, the diagnosis that always
I don't think a broken mount would cause anything severe like "shaking and shuddering". Usually, it might cause a wobble or shimmey, if you can understand the differences in degree of motion.
But I agree, that it sounds much