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                                                                      EXHIBIT 11

                   Quaker State Corporation and Subsidiaries

                 STATEMENT re COMPUTATION OF PER SHARE EARNINGS

                      (in thousands except per share data)


<TABLE>
<CAPTION>
                                                                             YEAR ENDED DECEMBER 31,
                                                                    -----------------------------------------
                                                                      1995             1994            1993
                                                                      ----             ----            ----
<S>                                                                 <C>               <C>            <C>
1. Net income.....................................................  $12,100           $18,766        $13,702
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2. Average number of shares of capital stock outstanding..........   32,119            28,368         27,203
                                                                  
3. Shares issuable upon exercise of dilutive stock options        
    outstanding during the year, based on average market          
    prices........................................................      107                91             31
                                                                  
4. Shares issuable upon exercise of dilutive stock options        
    outstanding during the year, based on higher of               
    average or year-end prices....................................      121                96             49
                                                                  
5. Average number of capital and capital equivalent shares        
    outstanding (2 + 3)...........................................   32,226            28,459         27,234
                                                                    =========================================
                                                                  
6. Average number of capital shares outstanding, assuming                          
    a full dilution (2 + 4).......................................   32,240            28,464         27,252
                                                                    =========================================
                                                                  
7. Net income per capital and equivalent share                    
    (1 divided by 5)..............................................  $  0.38           $  0.66        $  0.50
                                                                    =========================================
                                                                  
8. Net income per capital share, assuming full dilution           
    (1 divided by 6)..............................................  $  0.38           $  0.66        $  0.50
                                                                    =========================================
</TABLE>