Ashless lubricating oil with high oxidation stability

An ashless hydraulic fluid or an ashless paper machine oil, comprising:

• a. between 1 and 99.8 weight percent based on the total lubricating oil of
• a base oil having:
• i. greater than 90 wt % saturates,
• ii. less than 10 wt % aromatics,
• iii. less than 0.03 wt % sulfur,
• iv. a sequential number of carbon atoms,
• v. 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, and
• vi. a base oil viscosity index greater than 150;
• b. between 0.05 and 5 weight percent based on the total lubricating oil of an ashless antioxidant additive concentrate;
• and
• c. less than 0.5 weight percent based on the total lubricating oil of a viscosity index improver;
• wherein the ashless hydraulic fluid or ashless paper machine oil has:
• i. a lubricating oil viscosity index greater than 155;
• and
• ii. a result of greater than 600 minutes in the rotary pressure vessel oxidation test by ASTM D 2272-02 at 150 degrees C.