Stearic acid, labeled with radioactive carbon and hydrogen, was used as a model antisquawk agent in automatic transmission studies. The antisquawk agent is adsorbed on the clutch plates in the transmission. The surface coverage of the clutch plates by stearic acid drops abruptly as the transmission begins to squawk. Evidence is presented which support the conclusion that this decreased surface coverage is due to the formation of other polar compounds in the oil. These compounds compete with stearic acid for adsorption sites.