1999 Subaru Impreza Owner's Manual - Page 278

Oil grade: API classification GL-5 SAE viscosity No. and Applicable Temperature OM-H0205 Automatic transmission fluid WARNING Never let automatic transmission fluid contact your eyes because automatic transmission fluid can be harmful to your eyes. If automatic transmission fluid gets in your eyes, immediately flush them thoroughly with clean water. For safety, when performing this work, wearing eye protection is advisable. The automatic transmission fluid expands largely as its temperature rises; the fluid level differs according to fluid temperature. Therefore, there are two different scales for checking the level of hot fluid and cold fluid on the dipstick. Though the fluid level can be checked without warming up the fluid on the "COLD" side, we recommend checking the fluid level when the fluid is operating temperature. 10-22