Abstract: A method to stabilize a polyoxyalkylene polyether polyol against oxidative degradation by including therein an oligomeric sterically hindered phenol, namely phenol, 4-alkyl-, reaction products with dicyclopentadiene and isobutylene, having the formula I: wherein n is an integer ranging from 0 to 10, R is an alkyl group with 12 carbon atoms or less, as an antioxidant stabilizer, optionally in combination with other antioxidants, to said polyether polyol. This invention further relates to polyols stabilized by the method of this invention and to stabilized polyurethanes prepared from such stabilized polyols or stabilizers component.