Just as FYI...
Quicken.com (http://investing.quicken.com/public/view_headline.asp?symbol=CVX&documentKey=600-201103311530BIZWIRE_USPRX____BW5032-1)
http://www.deloperformance.com/products/greases.aspx#greaseESI (http://www.deloperformance.com/products/greases.aspx#greaseESI)
May be of interest for the sake of reducing total maintenance costs.