Since the 1950s, automotive enthusiasts have known the benefit of draining transmission fluid and and flushing out grime from time to time. How often you should flush transmission fluid depends on who you ask, but sooner is always better.
Most manufacturers recommend that you flush transmission fluid every 50,000 to 75,000 miles, according to Autos.com. Automotive experts, such as those at Aastro Transmission in Tucson, Arizona, suggest flushing transmission fluid as soon as every 12,000 miles.
Transmission fluid usually needs to operate between 175 and 190 degrees Celsius, according to AA1Car. In hot areas, such as the southwest, you may need to change every 30,000 miles or earlier. Every 20-degree increase cuts the life of transmission fluid in half.
Over time, dirt builds up in the transmission as the fluid breaks down. Flushing transmission fluid gets rid of this buildup and prevents problems, such as jerking. Also flushing at least every 30,000 miles means you can wait to change your transmission filter every 60,000 to 100,000 miles, according to AA1Car.
