Patent ID: 7547666

Claim:
An ashless hydraulic fluid or an ashless paper machine oil, comprising: a. a base oil having: i. greater than 90 wt % saturates, ii. less than 10 wt % aromatics, iii. a viscosity index greater than 120, iv. less than 0.03 wt % sulfur, v. a sequential number of carbon atoms, and vi. greater than 35 wt % total molecules with cycloparaffinic functionality or a traction coefficient less than or equal to 0.021 when measured at a kinematic viscosity of 15 cSt and at a slide to roll ratio of 40 percent; b. an ashless antioxidant additive concentrate; and c. less than 0.5 weight percent based on the total lubricating oil of a viscosity index improver; d. wherein the ashless hydraulic fluid or ashless paper machine oil has a lubricating oil viscosity index greater than 155 and a result of greater than 600 minutes in the rotary pressure vessel oxidation test by ASTM D 2272-02 at 150 degrees C.