EXHIBIT 5.1
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             [LETTERHEAD OF WILSON SONSINI GOODRICH & ROSATI]


                               July 24, 2001



TRIMBLE NAVIGATION LIMITED
645 North Mary Avenue
Sunnyvale, California 94088

        RE:  REGISTRATION STATEMENT ON FORM S-8
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Ladies and Gentlemen:

     We have acted as counsel to Trimble Navigation Limited and have examined
the Registration Statement on Form S-8 to be filed by you with the Securities
and Exchange Commission on or about July 24, 2001 (the "Registration
Statement"), in connection with the registration under the Securities Act of
1933, as amended, of 450,000 additional shares of your Common Stock reserved
for issuance under the 1993 Stock Option Plan (the "Plan") of Trimble
Navigation Limited.  As your legal counsel, we have examined the proceedings
taken and proposed to be taken in connection with the issuance, sale, and
payment of consideration for the shares to be issued under the Plan.

     It is our opinion that, when issued and sold in the manner referred to in
the Plan and pursuant to the agreements which accompany the Plan, the shares
will be legally and validly issued, fully paid, and non-assessable.

     We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement and any amendments thereto.


                                               Very truly yours,

                                               WILSON SONSINI GOODRICH & ROSATI
                                               Professional Corporation




                                               By:    /s/ JOHN B. GOODRICH
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                                                        John B. Goodrich