I was able to fix the rattle in my Maxxair fan on my camper van. Although the company will provide you with a free mod kit (previous video):
• Maxxair Maxxfan rattle...
It did not solve my rattle.
In this video, I'll walk you through my troubleshooting steps. Maybe what I discovered to fix mine will help you fix yours!
Maxxfan stats I picked up from their customer support line:
7A draw at startup
1.2A at low speeds
5A at high speeds
5A fuse should be good
lid motor load 0.5 N.m (newton meters), might be enough strength to lift a car window
motor rated for 10,000 cycles (up + down = 1 cycle)