Totally agree with anthonynelson about the oiling. I used the same heavy-duty one for my old truck's door hinges. A few drops of 3-in-1 oil every few months kept it from ever squeaking. That thing still works like new after a decade.
Used that exact same 3-in-1 on my lawnmower wheels last summer. Got tired of the squeaking every time I pushed it around the yard, so I just gave each wheel a couple drops. Haven't heard a peep since then, and that was almost a year ago. Honestly, it's way cheaper than buying a whole new mower or taking it to a shop. People sleep on basic maintenance, but a little oil goes a long way.