: Valve stem caps - color?

04-10-10, 12:22 PM
My recently purchased 07 ESV has a green color on the tips of the three of the valve caps. The 4th one, RR, is plain. What are they supposed to be?

04-10-10, 12:29 PM
They most likely have nitrogen...google the benefits of nitrogen filled tires...they are suppose to save fuel and of course you never have to fill them...I think everyone will argue If the benefits exist....I happy that I don't have to fill my tires and TPMS never goes off anymore since I changed.