2008 GMC Sierra 1500 Pickup Owner's Manual - Page 334

Hot Check Procedure Use this procedure to check the transmission fluid level when the transmission fluid temperature is between 160°F and 200°F (71°C and 93°C). The hot check is the most accurate method to check the fluid level. The hot check should be performed at the first opportunity in order to verify the cold check. The fluid level rises as fluid temperature increases, so it is important to ensure the transmission temperature is within range. 1. Locate the transmission dipstick at the rear of the engine compartment, on the passenger side of the vehicle. The dipstick handle has this graphic. See Engine Compartment Overview on page 5-12 for more information. 4. Check both sides of the dipstick, and read the lower level. Repeat the check procedure to verify the reading. 2. Flip the handle up, and then pull out the dipstick and wipe it with a clean rag or paper towel. 3. Install the dipstick by pushing it back in all the way, wait three seconds, and then pull it back out again. 5. Safe operating level is within the HOT cross hatch band on the dipstick. If the fluid level is not within the HOT band, and the transmission temperature is between 160°F and 200°F (71°C and 93°C), add or drain fluid as necessary to bring the level into the HOT band. If the fluid level is low, add only enough fluid to bring the level into the HOT band. It does not take much fluid, generally less than one pint (0.5L). Do not overfill. 6. If the fluid level is in the acceptable range, push the dipstick back in all the way, then flip the handle down to lock the dipstick in place. 5-22