Product review (1 stars): Fan motor doesn't last long.
As another reviewer mentioned, This is way over priced for what you get.
I've had my Maytag upright freezer now for 5 1/2 years now. This is the 2nd fan I had to put in since. The first one went out without warning.  Lost $1500.00 of food. Now this fan is making noise. Both the replacement fans and the original fan were Panansonic exactly like this one.
The freezer is great, the evaporator fan is crap. Wish I could buy a better quality fan.

After removing the fan and inspecting what was wrong, the fan motor is ok it is the shaft or the fan that is allowing the fan to move toward the motor allowing  the fan to hit the bracket nuts.
What I did was reverse the bracket mounting screws,  put the nuts on the opposite end to get a lot more clearance and raised the fan. We'll see how that works. But still something should be done not allow the fan to slide down the shaft.
So if you have a noisy fan that would be the first thing to definitely check.