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                                                                   EXHIBIT 31(b)

                                  CERTIFICATION

I, Jean Blackwell, Vice President and Chief Financial Officer of Cummins, Inc.
(Cummins), certify that:

1.       I have reviewed this annual report on Form 10-K of Cummins;

2.       Based on my knowledge, this annual report does not contain any untrue
         statement of a material fact or omit to state a material fact necessary
         to make the statements made, in light of the circumstances under which
         such statements were made, not misleading with respect to the period
         covered by this annual report;

3.       Based on my knowledge, the financial statements, and other financial
         information included in this annual report, fairly present in all
         material respects the financial condition, results of operations and
         cash flows of Cummins as of, and for, the periods presented in the
         annual report;

4.       Cummins' other certifying officer and I are responsible for
         establishing and maintaining disclosure controls and procedures (as
         defined in Exchange Act Rules 13a-14 and 15d-14) for Cummins and we
         have:

         a)       designed such disclosure controls and procedures to ensure
                  that material information relating to Cummins, including its
                  consolidated subsidiaries, is made known to us by others
                  within those entities, particularly during the period in which
                  this annual report is being prepared;

         b)       evaluated the effectiveness of Cummins' disclosure controls
                  and procedures as of a date within 90 days prior to the filing
                  date of this annual report (the "Evaluation Date"); and

         c)       presented in this annual report our conclusions about the
                  effectiveness of the disclosure controls and procedures based
                  on our evaluation as of the Evaluation Date;

5.       Cummins' other certifying officer and I have disclosed, based on our
         most recent evaluation, to Cummins' auditors and the Audit Committee of
         Cummins' Board of Directors (or persons performing the equivalent
         function):

         a)       all significant deficiencies in the design or operation of
                  internal controls which could adversely affect Cummins'
                  ability to record, process, summarize and report financial
                  data and have identified for Cummins' auditors any material
                  weaknesses in internal controls; and

         b)       any fraud, whether or not material, that involves management
                  or other employees who have a significant role in Cummins'
                  internal controls; and

6.       Cummins' other certifying officer and I have indicated in this annual
         report whether or not there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.


Date: July 29, 2003


                    /s/ Jean Blackwell
                    ---------------------------------
                    Jean Blackwell
                    Title: Vice President and Chief Financial Officer