What type of lubrication should I use on a squeaky swing set?
Since this is exterior, and I'd be too lazy to oil it after the first time, I'd use grease. It's the preferred maritime lubricant, and that's good enough for me.

White Lithium Grease –joneakes.com


  Lithium Grease is that thick white grease you often find packed into bearing housings. It is the workhorse of the lubricants and can take high temperatures and pressures. If you have a grease housing which will hold extra grease, using a thick lithium grease from a tube or a can is the best thing to do. They have now come out with Lithium spray greases. These are great for outdoor uses, tending to be thicker and stay put longer under the rigors of outdoor conditions than other sprays, but they are not intended to replace the even thicker grease that you pack into a gear box. They are definitely a grease and will stain clothing as well as attract dust when used openly, so although a great lubricant, not the best product for a bicycle chain. Be sure to shake the can well before using.


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