Squeaky Swings at My Local Park

My son and I visit a local park about three times each week. He really enjoys the swings. The problem is, the swings squeak very loudly when they're used. They're so loud, I'm surprised they haven't resulted in a car crash nearby. Before we went earlier today, I picked up an off-brand can of lubricant, like WD-40. It's the Dollar General brand. Honestly, it's probably just as good. I told him that I would buy him some for his new bike, so now he has some. There are seven swings in all, two of which are bucket swings (for babies), and one is a large seat-like swing that's big enough for an adult. After I sprayed them, there were four or five kids who came running over to swing. They were excited to finally swing without the ear-shattering noise. It had become obvious that no one working for the city (parks and recreation or otherwise) was going to do this. Problem solved!