White Lithium Grease has been working very well for me in all the temperatures I shoot and hunt in, and best of all, it stays in place without migrating away from where it's needed like oils can, it helps protect against rust, and it's cheap. What's not to love?
I've used Lithium Grease on my tractors for ever, and their high temp, metal to metal contact seems to do just fine with it.
Here is a couple descriptions google found;
White Lithium Grease is an all-purpose white lubricant for metal-to-metal and metal-to-plastic applications. This lubricant protects against rust, makes surfaces friction-free and withstands moisture and high heat.
Most lubricating greases are mixtures of an oil and a soap. ... Grease made with lithium soap ("lithium grease") adheres particularly well to metal, is non-corrosive, may be used under heavy loads, and exhibits good temperature tolerance.
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