Symptoms of a Clogged Transmission Filter
A clogged automatic transmission oil filter causes a noticeable delay while shifting from Park into other gears. If the transmission has a drawn-out and delayed shift from Park to Reverse while backing up, suspect low oil pressure. Low pressure causes issues shifting into other gears as well.
The transmission oil filter removes damaging debris and abrasives from the automatic transmission fluid. The debris collects, reducing flow and causing low oil pressure to the valve body. It results in transmission oil pump starvation and low line pressure. Steel mesh screens and surface filters are particularly vulnerable to blockage and are replaced at regular service intervals.
The filters are in the transmission's oil pan and mounted to the valve body. Transmission fluid is drawn through the filter before entering the valve body. It cleans the fluid before it enters the pump and travels through the lubrication system.
The filter protects the oil pump, transmission shafts, bushings, and bearings from harmful contaminants and debris. Additional filters in the transmission cooler line provide additional protection.