EXHIBIT 12.1 PACCAR Financial Corp. COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES PURSUANT TO SEC REPORTING REQUIREMENTS (Thousands of Dollars) Three Months Ended March 31 1998 1997 ------------------------------------- FIXED CHARGES Interest expense $ 25,949 $ 24,608 Portion of rentals deemed interest 76 59 ------------------------------------- TOTAL FIXED CHARGES $ 26,025 $ 24,667 ------------------------------------- ------------------------------------- EARNINGS Income before taxes $ 11,791 $ 12,744 Fixed charges 26,025 24,667 ------------------------------------- EARNINGS AS DEFINED $ 37,816 $ 37,411 ------------------------------------- ------------------------------------- RATIO OF EARNINGS TO FIXED CHARGES 1.45x 1.52x The method of computing the ratio of earnings to fixed charges shown above complies with SEC reporting requirements but differs from the method called for in the Support Agreement between the Company and PACCAR Inc. See Exhibit 12.2. -11-