Recommended Every Five Years

Through normal operation, the bearings, input and output shaft gears, and gear teeth in manual transmissions, differentials, and AWD systems are subjected to intense stress and heat and constant shearing of metal components. The result is chipping, thinning of fluid, flaking of bearings, and gear teeth which can result in looseness or binding. Gear teeth will become pitted and worn. Synchronizer sleeves may become scored so that they do not move freely. These conditions produce a noisy, hard-shifting transmission, excessive noise, and clunking in differential units, and eventual failure.