Checking the transmission fluid level on automatic transmissions is alittle different than checking the engine oil. On most vehicles, the engine has to be running at operating temperatures with the transmission in park. The dipstick is then pulled out, and the fluid level is checked by looking at the lines on the dipstick.

   Transmission fluid should be changed / flushed every 30,000 miles depending on the severity of driving. If the vehicle is driven normal, then this applies, if the vehicles is a work vehicle, then it should be changed every 15,000 miles. The transmission filter should be changed every 60,000 miles. Most automatic transmissions hold 12 quarts or more.