My trailer is a 2008. I made one trip of 800 miles just after I got it. Otherwise all our camping trips are about 40 miles or less. I don't think I have 5000 miles total on the trailer. So the que...
I just inspected and repacked mine after 4 years (approximately 19,000 miles). The bearings were in great shape. The brakes needed a lot of adjustment, easy to do it all at the same time. I also replaced all four tires. Aside from the brakes, I do not believe this is a yearly maintenance thing.