I have a BBQ pit that I had made about 20 years ago. The lid on it is very heavy but has been just fine until about a year ago and it is getting increasingly hard to open. I need to lubricate the hinges on the thing but I need to figure out what to use. I know that WD40 is not going to help because it will just evaporate. Wjhat is a good type of lubricant to use for that and how do I cox it down into the hinge?