However, sometimes the need to replace the working fluid may arise, for example, when the quality of the working fluid in the gearbox deteriorates after it overheats, when repairing the gearbox, etc.
Replacing the working fluid in an automatic transmission requires certain skills, so for a complete replacement of the working fluid, contact a specialized service. For an automatic transmission, the manufacturer recommends the working fluid GM 93740313 4SP AVEO/U\CETTI or DEXRON VI.
1. Start the engine and warm up the gearbox. The temperature of the fluid in the gearbox should be 70-80°C. To speed up the warming up, you can take the car for a short drive. Usually, at an ambient temperature of 20°C, a 10-minute drive in a calm driving mode is enough.
2. Place the vehicle on a level horizontal surface. Apply the parking brake. With the engine idling, press the brake pedal and move the selector lever from position "P" to position "D". Keeping the brake pedal pressed, let the vehicle run for 1-2 minutes in position "D", then move the selector for 3-4 seconds successively to each of the operating modes and set it to position "P" or "N". The engine must be running during the test.
3. Even a small amount of mechanical impurities should not enter the working fluid of the gearbox, therefore, before removing the fluid level indicator (dipstick), carefully wipe off any dirt from the surface around the measuring tube,
4. Remove the pointer (dipstick), wipe with a clean cloth and reinsert. Remove the pointer (dipstick) again.
5. The fluid level should be in the range B between the upper and lower limits of the "HOT" scale on the dipstick.
Warning: If the level check is forced to be carried out in a cold gearbox, use the C scale on the dipstick. The range A between the marks is advisory in nature and should not be used to accurately determine the level of the working fluid in the automatic transmission. At the first opportunity, repeat the check in accordance with the recommendations in paragraph 1.
6. If the fluid level approaches the lower limit of the "NOT" scale or is lower than it, add fluid. The working fluid is added through the level gauge tube in small portions. Add only the working fluid recommended by the manufacturer.
7. After adding fluid, be sure to check its level again. Do not exceed the maximum permissible level, as this may cause the gearbox to fail.
[The original text can be found on the website «ChevyMan»]