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                                                                     EXHIBIT 4.1

                                 TRUST AGREEMENT

         TRUST AGREEMENT, dated as of March 5, 2004, between SLM Funding LLC, a
Delaware limited liability company (the "Depositor"), and Chase Manhattan Bank
USA, National Association ("Chase"), a national banking corporation, not in its
individual capacity but solely as Eligible Lender Trustee (the "Trustee"). The
Depositor and the Trustee hereby agree as follows:

         1.       The trust created hereby shall be known as SLM Student Loan
Trust 2004-2 (the "Trust") in which name the Trustee may conduct the business of
the Trust, make and execute contracts, and sue and be sued.

         2.       The Depositor hereby assigns, transfers, conveys and sets over
to the Trustee the sum of $100. The Trustee hereby acknowledges receipt of such
amount in trust from the Depositor, which amount shall constitute the initial
trust estate. The Trustee hereby declares that it will hold the trust estate in
trust for the Depositor. It is the intention of the parties hereto that the
Trust created hereby constitute a business trust under Chapter 38 of Title 12 of
the Delaware Code, 12 Del. C. Section 3801 et seq. and that this document
constitute the governing instrument of the Trust. The Trustee is hereby
authorized and directed to execute and file a certificate of trust with the
Delaware Secretary of State in the form attached hereto.

         3.       The Depositor and the Trustee will enter into an amended and
restated Trust Agreement, satisfactory to each such party, to provide for the
contemplated operation of the Trust created hereby. Prior to the execution and
delivery of such amended and restated Trust Agreement, the Trustee shall not
have any duty or obligation hereunder or with respect to the trust estate,
except as otherwise required by applicable law or as may be necessary to obtain
prior to such execution and delivery any licenses, consents or approvals
required by applicable law or otherwise.

                  (a)      Except as otherwise expressly required in Sections 2
and 3 of this Trust Agreement, the Trustee shall not have any duty or liability
with respect to the administration of the Trust, the investment of the Trust's
property or the payment of dividends or other distributions of income or
principal to the Trust's beneficiaries, and no implied obligations shall be
inferred from this Trust Agreement on the part of the Trustee. The Trustee shall
not be liable for the acts or omissions of the Depositor or any other person who
acts on behalf of the Trust nor shall the Trustee be liable for any act or
omission by it in good faith in accordance with the directions of the Depositor.

                  (b)      The Trustee accepts the trusts hereby created and
agrees to perform its duties hereunder with respect to the same but only upon
the terms of this Trust Agreement. The Trustee shall not be personally liable
under any circumstances, except for its own willful misconduct or gross
negligence. In particular, but not by way of limitation:

                           i.       The Trustee shall not be personally liable
for any error of judgment made in good faith by an officer or employee of the
Trustee;

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                           ii.      No provision of this Trust Agreement shall
require the Trustee to expend or risk its personal funds or otherwise incur any
financial liability in the performance of its rights or duties hereunder, if the
Trustee shall have reasonable grounds for believing that repayment of such funds
or adequate indemnity against such risk or liability is not reasonably assured
or provided to it;

                           iii.     Under no circumstance shall the Trustee be
personally liable for any representation, warranty, covenant or indebtedness of
the Trust;

                           iv.      The Trustee shall not be personally
responsible for or in respect of the genuineness, form or value of the Trust
property, the validity or sufficiency of this Trust Agreement or for the due
execution hereof by the Depositor;

                           v.       In the event that the Trustee is unsure as
to the course of action to be taken by it hereunder, the Trustee may request
instructions from the Depositor and to the extent the Trustee follows such
instructions in good faith it shall not be liable to any person. In the event
that no instructions are provided within the time requested by the Trustee, it
shall have no duty or liability for its failure to take any action or for any
action it takes in good faith;

                           vi.      All funds deposited with the Trustee
hereunder may be held in a non-interest bearing trust account and the Trustee
shall not be liable for any interest thereon or for any loss as a result of the
investment thereof at the direction of the Depositor;

                           vii.     To the extent that, at law or in equity, the
Trustee has duties and liabilities relating thereto to the Depositor or the
Trust, the Depositor agrees that such duties and liabilities are replaced by the
terms of this Trust Agreement.

                  (c)      The Trustee shall incur no liability to anyone in
acting upon any document believed by it to be genuine and believed by it to be
signed by the proper party or parties. The Trustee may accept a certified copy
of a resolution of the board of directors or other governing body of any
corporate party as conclusive evidence that such resolution has been duly
adopted by such body and that the same is in full force and effect. As to any
fact or matter the manner of ascertainment is not specifically prescribed
herein, the Trustee may for all purposes hereof rely on a certificate, signed by
the Depositor, as to such fact or matter, and such certificate shall constitute
full protection to the Trustee for any action taken or omitted to be taken by it
in good faith in reliance thereon.

                  (d)      In the exercise or administration of the trusts
hereunder, the Trustee (i) may act directly or, at the expense of the Depositor,
through agents or attorneys, and the Trustee shall not be liable for the default
or misconduct of such attorneys or agents if such agents and attorneys shall
have been selected by the Trustee in good faith, and (ii) may, at the expense of
the Depositor, consult with counsel, accountants and other experts, and it shall
not be

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liable for anything done, suffered or omitted in good faith by it in accordance
with the advice or opinion of any such counsel, accountants or other experts.

                  (e)      Notwithstanding anything contained herein to the
contrary, neither Chase nor the Trustee shall be required to take any action in
any jurisdiction other than the State of Delaware if the taking of such action
will (i) require the consent or approval or authorization or order of or the
giving of notice to, or the registration with or the taking of any other action
in respect of, any state or other governmental authority or agency of any
jurisdiction other than the State of Delaware, (ii) result in any fee, tax or
other governmental charge under the laws of any jurisdiction or any political
subdivision thereof in existence becoming payable by Chase, or (iii) subject
Chase to personal jurisdiction in any jurisdiction other than the State of
Delaware for causes of action arising from acts unrelated to the consummation of
the transactions by Chase or the Trustee, as the case may be, contemplated
hereby.

                  (f)      Except as expressly provided in this Section 4, in
accepting and performing the trusts hereby created, the Trustee acts solely as
trustee hereunder and not in its individual capacity, and all persons having any
claim against the Trustee by reason of the transactions contemplated by this
Trust Agreement shall look only to the Trust's property for payment or
satisfaction thereof.

         4.       The Depositor hereby agrees to (i) compensate the Trustee for
its services hereunder in an amount separately agreed to by the Depositor and
the Trustee, (ii) reimburse the Trustee for all reasonable expenses (including
reasonable fees and expenses of counsel and other experts) and (iii) indemnify,
defend and hold harmless the Trustee and any of the officers, directors,
employees and agents of the Trustee (the "Indemnified Persons") from and against
any and all losses, damages, liabilities, claims, actions, suits, costs,
expenses, disbursements (including reasonable fees and expenses of its counsel),
taxes and penalties of any kind and nature whatsoever (collectively,
"Expenses"), to the extent that such Expenses arise out of or are imposed upon
or asserted at any time against such Indemnified Person with respect to the
performance of this Trust Agreement, the creation, operation or termination of
the Trust or the transactions contemplated hereby; provided, however, that the
Depositor shall not be required to indemnify any Indemnified Person for any
Expenses which are a result of the willful misconduct, bad faith or gross
negligence of such Indemnified Person. The obligations of the Depositor under
this Section 5 shall survive the termination of this Trust Agreement.

         5.       The Trustee may resign upon thirty days prior notice to the
Depositor. If no successor has been appointed within such thirty day period, the
Trustee may, at the expense of the Trust, petition a court of competent
jurisdiction to appoint a successor trustee.

         6.       This Trust Agreement constitutes the entire agreement between
the parties hereto with respect to the subject matter hereof, and supersedes all
prior agreement and understandings between the parties.

         7.       This Trust Agreement shall be governed by and construed in
accordance with the laws of the State of Delaware, without reference to is
conflict of law provisions, and the obligations, rights and remedies of the
parties hereunder shall be determined in accordance with

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such laws.

         8.       This Trust Agreement may be executed in one or more
counterparts, each of which when so executed shall be an original and all of
which when taken together shall constitute but one and the same instrument.

                            [signature page follows]

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         IN WITNESS WHEREOF, the parties hereto have caused this Trust Agreement
to be duly executed by their respective officers hereunto duly authorized, as of
the day and year first above written.

                                    SLM FUNDING LLC, as Depositor

                                    By: /s/ MARK L. HELEEN
                                    Name:   Mark L. Heleen
                                    Title:  Vice President

                                    CHASE MANHATTAN BANK USA,
                                    NATIONAL ASSOCIATION , not in its
                                    individual capacity but solely as Eligible
                                    Lender Trustee

                                    By: /s/ JOHN J. CASHIN
                                    Name:   John J. Cashin
                                    Title:  Vice President

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                              CERTIFICATE OF TRUST
                                       OF
                          SLM STUDENT LOAN TRUST 2004-2

         THIS Certificate of Trust of SLM STUDENT LOAN TRUST 2004-2 (the
"Trust") is being duly executed and filed on behalf of the Trust by the
undersigned, as trustee, to form a statutory trust under the Delaware Statutory
Trust Act (12 Del. C. Section 3801 et seq.) (the "Act").

         1.       Name. The name of the statutory trust formed by this
Certificate of Trust is SLM STUDENT LOAN TRUST 2004-2.

         2.       Delaware Trustee. The name and business address of the trustee
of the Trust in the State of Delaware are the Chase Manhattan Bank USA, National
Association, c/o JP Morgan Chase, 500 Stanton Christiana Road, OPS4/3rd Floor,
Newark, Delaware 19713, Attn: Institutional Trust Services.

         3.       Effective Date. This Certificate of Trust shall be effective
upon filing.

         IN WITNESS WHEREOF, the undersigned has duly executed this Certificate
of Trust in accordance with Section 3811(a)(1) of the Act.

                                          CHASE MANHATTAN BANK
                                          USA, NATIONAL ASSOCIATION,
                                          not in its individual capacity but
                                          solely as Trustee

                                          By:___________________________
                                          Name:
                                          Title: