NAG1 Remove the cap from the fill tube. Actuate the parking brake. Start the engine and let it run at idle speed in selector lever position "P". Shift through the transmission modes several times with the vehicle stationary and the engine idling. Warm up the transmission, wait at least 2 minutes and check the oil level with the engine running. Insert special tool 9336 in up to the stop and pull out again, read off oil level, repeat if necessary. Check the transmission oil temperature. True transmission oil temperature can only be read by a scan tool with the transmission in the reverse or forward gear position. Tool 9336 has indicator marks every 10mm. Oil level varies by temperature, at 77° F / 40mm, 122° F/ 60mm, 158°F/ 75mm, 185°F/ 85mm. Add or remove oil as necessary and recheck the oil level. Once the oil level is correct, install dipstick tube cap.