Originally Posted By: bretfraz
Zymol is a very rare exception. Many of their products are made of natural ingredients which may separate or become moldy if they are exposed to high temps long term. Your expensive high-carnauba content waxes should probably be stored in the fridge if the mfr suggests it.
For the other 99.99999999% of the car care products on the market, they should be kept at reasonable temps, out of the sun, and sealed tightly. Many products will not perform correctly if they become frozen at some time. Others will become unstable if exposed to high heat. Any products exposed to these extremes should be disposed; they probably will not work as they should if used.
If you are not sure what the waxes have been exposed to, the best bet is to replace them. In the OP's case, we are talking about maybe $20 in products. New products will work best and may perform better than some old stuff that's been sitting around for a long time.
I agree with your assessment but storing any wax in a refrigerator seems to extend its shelf life from personal experience. At the least, it's no WORSE than storing it in the basement.
I only use carnauba-based waxes though so that might be my reasoning. And likely the 3M wax the OP has is a carnauba-based wax. I could be mistaken on that though.