If you are curious, or for sh*ts a giggles, you can suspend them in a pot of water, with an appropriate oven/meat thermometer, and see which one (or both) are not working correctly.
The temp printed on it is the temp at which it should start to open (=/- a few degrees. Fully open at about 10 to 12C deg above that.
2018 L5P Sierra 4x4 SB Denali
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Sold 2004.5 LLY Sierra 4x4 ECLB SLE
Last edited by OkDually; 12-16-2018 at 07:32 PM.