Before inspecting the compressor mounts, unplug
the freezer to avoid an electrical shock hazard.
The compressor sits on rubber mountings. Those
rubber mountings are designed to absorb vibration from the compressor.
As the mountings age, they can become hard or disintegrate. When
this happens, the compressor vibration is transmitted to the freezer
and it can be noisy. Replacing the mountings is easy to do.
The compressor is located in the rear. It may
be necessary to remove an access panel to get to the compressor.
Locate the compressor and remove the screw or
retaining clip (labeled "A" below) of just one of the
compressor mounts (labeled "B"). Using a pry bar, lift
up the compressor enough to slip out the rubber mount. Inspect
the mount for deterioration. The rubber should be firm but not
rigid. If the mount is crumbly or hard, it should be replaced.
Replace and tighten the compressor mount.
Repeat this step for each of the compressor
mounts.
Before inspecting the compressor mounts, unplug
the freezer to avoid an electrical shock hazard. 
