Castrol ATF DEX III is an automatic transmission and power steering fluid for use in GM automatic transmissions pre 2005 and in many automatic transmissions where Dexron® (II or III) or Mercon performance is required.


Recommended for many transmissions used in General Motors cars, Holden, Isuzu, Opel and Hydramatic® transmissions used in a range of vehicles. 

It is also suitable many earlier model Japanese vehicles where Dexron® type fluids are recommended. It is recommended for other transmissions where Dexron® and Dexron® II fluids are specified except Mercedes-Benz, ZF, BMW, Voith and Renk. 

Features & Benefits

  • Enhanced friction durability prolongs transmission life and promotes smooth shifting.
  • Increased resistance to oil oxidation and degradation.
  • Increased clutch band and clutch pack capacity.
  • Improved protection of copper and bronze components.


  • Dexron® III H, IID and II.
Also suitable for use where the following performance levels are specified
  • Holden HN 2126
  • Mazda M III Fluid
  • Ford Mercon IV
  • Allison C4
  • Ford M2C-138CJ
  • General Motors Type A Suffix A
Protector Series