1994 Chevrolet Astro Owner's Manual - Page 239

NOTICE: Too much or too little fluid can damage your transmission. Too much can mean that some the fluid could come out and fall on of hot engine parts or exhaust system, starting a Be sure to get fire. an accurate reading if you check transmission fluid. your Wait at least 30 minutes before checking the transmission fluid level if you have beendriving: 0 0 When outside temperaturesare above 90°F (32 " C). At high speed for quite a while. In heavy traffic - especially in hot weather. While pulling a trailer. 0 To get the right reading, the fluid should be at normal operating temperature, which is 180°Fto 200°F (82°C to 93°C). To check transmission fluid hot: Get the vehicle warmed up by driving about 15 miles(24 km) when outside temperatures are above 50°F (10"C). If it's colder than50°F (IOOC), drive the vehicle in "D" (3rd Gear) until the engine temperature gage moves and then remains steady ten minutes. for Then follow the hot check procedures. To check transmissionfluid cold: A cold check is made after the vehicle has been sitting for eight hours or more with the engine off and used only as a is reference. Let the engine run at idle five minutes if outside temperatures for are 50°F ( 10°C) ormore. If it's colder than 50°F (IOOC), you may haveto idle the engine longer. Should the fluid level be low during a cold check, you must perform a hot check before adding fluid. This will give you a more accurate readingof the fluid level. To check the fluid hot cold or Park your vehicle on a level place. With the parking brake applied, place the shift lever in "P" (Park). With your foot on the brake pedal, move the lever through each shift gear range, pausingfor about three seconds in each range. Then, position the shift lever in "P" (Park). 0 Let the engine runat idle for three minutes or more. 6-21