An apparatus for attenuation of fluid pressure pulses in a hydraulic system of an automatic transmission is provided. and at a pH of not more than 2 to obtain a solution L comprising cerium in the oxidation state III;b) adding at least one basic compound C to said solution L to obtain a solid F comprising at least one cerium compound;c) separating off said solid F comprising at least one cerium compound. Once the midsection is engaged, the pry arm is actuated by means of a lever arm which can be viewed as outwardly expanding jaws or jaw surfaces which have the effect of spreading or loosening the knot.