Automatic transmission fluid

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Automatic transmission fluid (ATF) is a hydraulic fluid that is essential for the proper functioning of vehicles equipped with automatic transmissions. Usually, it is coloured red or green to differentiate it from motor oil and other fluids in the vehicle.

This fluid is designed to meet the unique demands of an automatic transmission. It is formulated to ensure smooth valve operation, minimize brake band friction, facilitate torque converter function, and provide effective gear lubrication.

ATF is commonly utilized as a hydraulic fluid in certain power steering systems, as a lubricant in select 4WD transfer cases, and in modern manual transmissions.