EXHIBIT 12.1 PACCAR Financial Corp. COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES PURSUANT TO SEC REPORTING REQUIREMENTS (Thousands of Dollars) Nine Months Ended September 30 1998 1997 -------- -------- FIXED CHARGES Interest expense $ 82,774 $ 75,238 Portion of rentals deemed interest 528 187 -------- -------- TOTAL FIXED CHARGES $ 83,302 $ 75,425 -------- -------- -------- -------- EARNINGS Income before taxes $ 35,944 $ 38,451 Fixed charges 83,302 75,425 -------- -------- EARNINGS AS DEFINED $119,246 $113,876 -------- -------- -------- -------- RATIO OF EARNINGS TO FIXED CHARGES 1.43x 1.51x 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. -13-