How often should the automatic transmission fluid be changed?
(The following is excerpted from Carley’s Car Care Guide, c1996 Larry Carley) Most owners manuals say periodic fluid changes are not necessary. Yeah, right. That’s why transmission shops are making a fortune replacing burned out automatic transmissions. For optimum protection, change the fluid and filter about every 12,000 – 30,000 miles, depending on your owner’s manual recommendations. CAUTION: If the fluid in your transmission has never been changed and the transmission has more than 50,000 miles on it, it might be too late to change it! Changing the fluid on a high mileage transmission can sometimes lead to transmission problems because of accumulated varnish deposits and wear in the clutches. Why ATF Wears Out An automatic transmission creates a lot of internal heat through friction: the friction of the fluid churning inside the torque converter, friction created when the clutch plates engage, and the normal friction created by gears and bearings carrying their loads. It doesn t t
