EXHIBIT 10.29.2

                             SECURED PROMISSORY NOTE


$__________                                                   September __, 2001


         FOR VALUE RECEIVED,  this Secured Promissory Note (this "Note") is made
by    Probex     Corp.,     a     Delaware     corporation     ("Maker"),     to
_____________________________("Payee").  This  Note  is one of  the  "Notes"  as
defined in, and is entitled to the  benefits  of, that  certain  Loan  Agreement
("Loan  Agreement")  and  Intercreditor  and Security  Agreement  (the "Security
Agreement"), each dated of even date herewith.

         1.  Payments.  Maker  hereby  promises to pay to the order of Payee the
principal  sum  of  ___________________________   Dollars  ($______________)  at
______________________,  or such other place as Payee may designate from time to
time in  writing,  in  lawful  money of the  United  States  of  America  and in
immediately  available  funds,  together with  interest on the unpaid  principal
balance  hereof at the rate  provided  herein  from the date of this Note  until
payment in full of the indebtedness evidenced by this Note or conversion of this
Note as provided  for in Section 3 hereof.  This Note and all accrued and unpaid
interest  shall be due and  payable in one lump sum on  September  30, 2001 (the
"Maturity  Date"),  which shall be subject to automatic  extensions  as provided
below.  Any  payment  made under this Note  shall be applied  first to  interest
accrued  and  unpaid on the  outstanding  principal  balance  as of such date of
payment and then to the  outstanding  principal  balance due  hereunder.  If any
required payment in cash or Maker's common stock falls due on a Saturday, Sunday
or a national or state bank  holiday in Texas,  then such date shall be extended
to the next  succeeding day that is not a Saturday,  Sunday or national or state
bank holiday.

         2. Interest Rate. The principal  amount  outstanding  from time to time
hereunder  shall bear  interest  calculated on the basis of a 365-day year, at a
rate  equal to twelve  percent  (12%) per  annum or,  after an Event of  Default
hereunder, eighteen percent (18%) per annum.

         3. Conversion.  The outstanding  principal  balance and all accrued and
unpaid  interest  due under  this  Note at the  closing  on or before  the Final
Extension  Date (as  defined  below)  of the sale by Maker of its  preferred  or
common stock on customary terms for cash to be used to finance Maker's  proposed
Wellsville, Ohio facility, which results in proceeds to the Maker aggregating at
least $35 million,  excluding the outstanding principal balance and interest due
under  this  Note on the date  thereof,  following  or  simultaneously  with the
closing of a debt financing on customary terms under which Maker has drawn or is
currently  able to draw not less  than $80  million  for the  financing  of such
Wellsville,   Ohio   facility  (the   "Qualified   Equity   Financing"),   shall
automatically be converted into fully-paid and non-assessable  shares of Maker's
preferred or common stock identical in all respects as to those shares issued to
the purchasers in the Qualified Equity Financing. The number of shares issued to
Payee upon conversion of this Note shall be equal to the  outstanding  principal
balance and all accrued and unpaid  interest  due under this Note on the date of
the consummation of the Qualified Equity Financing divided by the purchase price
paid to  Maker  by such  purchasers  for  each  share  of  Maker's  stock in the
Qualified Equity Financing.

         4. Extension. The Maturity Date is subject to extension as follows:


                  (i)      If the Qualified  Equity Financing is not consummated
                           on or prior to the Maturity  Date,  the Maturity Date
                           shall be  extended  to October  31,  2001 (the "First
                           Extension   Date"),   and,  for  no  additional  cash
                           consideration,  the Maker  shall issue to Payee on or
                           prior to September 30, 2001, that number of shares of

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                           Maker's  common  stock  having  an  aggregate   value
                           (calculated  as provided  below) equal to twenty-five
                           percent (25%) of the  outstanding  principal  balance
                           and all  accrued and unpaid  interest  due under this
                           Note on the Maturity Date,  which issuance shall be a
                           condition to such extension;

                  (ii)     If the Qualified  Equity Financing is not consummated
                           on or prior to the First  Extension  Date,  the First
                           Extension Date shall be extended to November 30, 2001
                           (the "Second Extension Date"), and, for no additional
                           cash consideration, the Maker shall issue to Payee on
                           or prior to October 31,  2001,  that number of shares
                           of Maker's  common stock  having an  aggregate  value
                           (calculated  as provided  below) equal to ten percent
                           (10%) of the  outstanding  principal  balance and all
                           accrued  and unpaid  interest  due under this Note on
                           the First Extension  Date,  which issuance shall be a
                           condition to such extension; and

                  (iii)    If the Qualified  Equity Financing is not consummated
                           on or prior to the Second  Extension Date, the Second
                           Extension Date shall be extended to December 31, 2001
                           (the "Final Extension Date"),  and, for no additional
                           cash consideration, the Maker shall issue to Payee on
                           or prior to November 30, 2001,  that number of shares
                           of Maker's  common stock  having an  aggregate  value
                           (calculated  as provided  below)equal  to ten percent
                           (10%) of the  outstanding  principal  balance and all
                           accrued  and unpaid  interest  due under this Note on
                           the Second  Extension Date, which issuance shall be a
                           condition to such extension.

The shares of Maker's  common  stock  issued in  accordance  with this Section 4
shall be  deemed  issued  at a value  per  share  equal to the  lower of (x) the
average of the closing  share prices of Maker's  common stock as reported by the
American  Stock  Exchange on the ten (10)  trading  days that are three (3) days
prior to the relevant Extension Date; (y) if the Qualified Equity Financing is a
sale of Maker's  preferred  stock,  the  initial  conversion  price at which the
shares issued in the Qualified Equity Financing are convertible into the Maker's
common stock, if applicable; or (z) if the Qualified Equity Financing is sale of
Maker's  common  stock,  the purchase  price of such stock paid to Maker by such
purchasers.  At the time of each extension,  shares shall be issued based on the
price computed in accordance  with clause (x) above.  Certificates  representing
the  shares  of the  Maker's  common  stock  that the  Payee is  entitled  to in
accordance  with the  foregoing in excess of the number of shares  issued at the
time of  each  extension,  if  any,  shall  be  issued  to the  Payee  upon  the
consummation of the Qualified Equity  Financing;  provided,  that the absence of
stock certificates evidencing the shares of Maker's common stock shall in no way
limit or effect the  Payee's  right and title to such  shares of Maker's  common
stock.

         5. Use of  Proceeds.  Maker  and its  subsidiaries  shall  utilize  the
proceeds  from  this  Note for  general  working  capital  purposes  in a manner
consistent with the projections dated as of July 21, 2001,  previously  provided
to Payee. Maker agrees to implement,  or continue its application of, reasonable
cash flow  conversation  measures  that it believes are in its best  interest to
maximize the useful life of the proceeds received by the Maker hereunder.

         6. Event of Default.  An event of default  ("Event of  Default")  shall
exist if:

                   (a) Maker shall fail to pay any principal of, or any interest
on, this Note or any other amount payable under this Note,  when and as the same
shall become due and payable;

                  (b) any  representation  or warranty made or deemed made by or
on behalf of Maker in the Security  Agreement,  or any amendment or modification

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thereof or waiver thereunder, or in any report, certificate, financial statement
or other document furnished pursuant to or in connection the Security Agreement,
or any amendment or modification  thereof or waiver  thereunder,  shall prove to
have been incorrect when made or deemed made;

                   (c) Maker or any of its subsidiaries shall fail to observe or
perform any covenant, condition or agreement contained in the Security Agreement
or this Note;

                  (d) Maker or any of its  subsidiaries  shall  fail to make any
payment  (whether of principal or interest and  regardless of amount) in respect
of any  indebtedness,  individually  or in the aggregate,  in excess of $100,000
("Material Indebtedness"), when and as the same shall become due and payable;

                  (e) any event or condition occurs that results in any Material
Indebtedness  of  Maker or any of its  subsidiaries  becoming  due  prior to its
scheduled  maturity  or that  enables or permits  (with or without the giving of
notice, the lapse of time or both) the holder or holders of any indebtedness for
borrowed money of Maker or any of its  subsidiaries,  or any trustee or agent on
its or their behalf,  to cause any  indebtedness  for borrowed money of Maker or
any of its subsidiaries to become due, or to require the prepayment, repurchase,
redemption or defeasance thereof, prior to its scheduled maturity;

                  (f)  an  involuntary  proceeding  shall  be  commenced  or  an
involuntary  petition shall be filed seeking (i) liquidation,  reorganization or
other relief in respect of Maker or any of its  subsidiaries or their respective
debts,  or of a  substantial  part of its assets,  under any  federal,  state or
foreign bankruptcy, insolvency,  receivership or similar law now or hereafter in
effect or (ii) the appointment of a receiver, trustee, custodian,  sequestrator,
conservator or similar  official for Maker or any of its  subsidiaries  or for a
substantial part of any of their assets,  and, in any such case, such proceeding
or  petition  shall  continue  undismissed  for 60 days or an  order  or  decree
approving or ordering any of the foregoing shall be entered;

                  (g) Maker or any of its  subsidiaries  shall  (i)  voluntarily
commence any proceeding or file any petition seeking liquidation, reorganization
or other  relief  under any federal,  state or foreign  bankruptcy,  insolvency,
receivership  or similar law now or  hereafter  in effect,  (ii)  consent to the
institution  of, or fail to  contest  in a timely and  appropriate  manner,  any
proceeding or petition described in clause (f) of this Section,  (iii) apply for
or consent to the appointment of a receiver, trustee,  custodian,  sequestrator,
conservator or similar  official for Maker or any of its  subsidiaries  or for a
substantial  part of any of their  assets,  (iv)  file an answer  admitting  the
material allegations of a petition filed against it in any such proceeding,  (v)
make a general  assignment  for the benefit of creditors or (vi) take any action
for the purpose of effecting any of the foregoing;

                   (h) Maker or any of its  subsidiaries  shall  become  unable,
admit in writing its inability or fail generally to pay its debts as they become
due;

                  (i) one or more  judgments  for the  payment  of  money  in an
aggregate  amount in excess of $25,000 shall be rendered against Maker or any of
its subsidiaries  and the same shall remain  undischarged for a period of thirty
(30) days during which execution shall not be effectively  stayed, or any action
shall be legally taken by a judgment  creditor to attach or levy upon any assets
of Maker or any of its subsidiaries to enforce any such judgment;

                  (j) any  lien  purported  to be  created  under  the  Security
Agreement  shall  cease to be, or shall be  asserted  by Maker or any  affiliate
thereof not to be, a valid and perfected  lien on the  Collateral (as defined in
the Security  Agreement),  with the priority required by the Security Agreement,
except (i) as a result of the sale or other  disposition  of the Collateral in a
transaction  permitted  under the Security  Agreement or (ii) as a result of the
Collateral  Agent's  failure to maintain  possession of any promissory  notes or
other instruments delivered to it under the applicable Security Agreement;

                  (k) there shall occur, in the reasonable  judgment of Payee, a
material adverse change in the business,  assets or prospects of Maker or any of
its subsidiaries after the date hereof;

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                   (l) there shall occur any  material  loss,  theft,  damage or
destruction of any of Maker's or any of its subsidiaries' property or assets not
fully covered by insurance;

                   (m) there shall occur a cessation  of a  substantial  part of
the  business  of  Maker  or  any  of  its   subsidiaries  for  a  period  which
significantly  effects its  capacity to continue  its  business on a  profitable
basis; or Maker or any of its  subsidiaries  shall suffer the loss or revocation
of any license or permit now held or hereafter acquired by it which is necessary
to the continued or lawful operation of its respective business; or Maker or any
of its  subsidiaries  shall be enjoined,  restrained  or in any way prevented by
court,  governmental or administration order from conducting all or any material
part of its respective  business affairs; or any material part of Maker's or any
of its subsidiaries'  property shall be taken through  condemnation or the value
of such property shall be materially impaired through condemnation;

                   (n)  Maker's  common  stock  shall  cease to be listed on any
national securities exchange or reported by the NASDAQ National Market System or
Small Cap Market System; or

                   (o) Maker shall  receive a "going  concern"  opinion from its
independent  auditors,  or,  after  giving  effect  to  proceeds  of this  Note,
otherwise  does  not  have  sufficient   available  working  capital  to  ensure
viability.


         7.       Remedies Upon an Event of Default.

                  (a)      Acceleration.

                          (i) If an Event of Default  described in paragraph (f)
or (g) of Section 6 hereof shall occur,  this Note and the obligation to pay the
principal and accrued interest hereunder shall automatically  become immediately
due and payable without any action or notice on the part of the Payee.

                         (ii) If an Event of Default  described in  paragraphs
(a),  (b),  (d),  (e),  (h),  (i),  (j), (k), (l) or (m) of Section 6 hereof has
occurred,  and at any time thereafter  during the continuance of such event, the
Payee may declare the then outstanding  amounts  hereunder to be due and payable
in whole (or in part,  in which case any principal not so declared to be due and
payable may  thereafter  be declared to be due and  payable) and  thereupon  the
principal of the amounts  hereunder so declared to be due and payable,  together
with  accrued  interest  thereon  and all  other  obligations  of Maker  accrued
hereunder,  shall  become  due and  payable  immediately,  without  presentment,
demand,  protest or other notice of any kind,  all of which are hereby waived by
Maker;

                         (iii) If any other Event of Default described in
Section 6 has occurred,  Payee shall  deliver  notice of such event to Maker and
thereupon  Maker  shall have  twenty  (20)  calendar  days to cure such Event of
Default, or Events of Default ("Cure Period").  If Maker does not cure the Event
of  Default,  or Events of  Default,  during the Cure  Period,  then at any time
thereafter  during the continuance of such event, the Payee may declare the then
outstanding  amounts  hereunder  to be due and payable in whole (or in part,  in
which case any principal not so declared to be due and payable may thereafter be
declared to be due and payable) and thereupon the principal amounts hereunder so
declared to be due and payable,  together with accrued  interest thereon and all
other  obligations  of Maker  accrued  hereunder,  shall  become due and payable
immediately,  without presentment,  demand, protest or other notice of any kind,
all of which are hereby waived by Maker.

                  (b) Remedies  Cumulative.  The remedies available to Payee, as
provided  herein,  shall  be  cumulative  and  concurrent,  and  may be  pursued
singularly,  successively or together,  at the sole discretion of Payee, and may
be exercised as often as occasion  therefor  shall arise.  No act of omission or
commission of Payee,  including  specifically any failure to exercise any right,
remedy or recourse,  shall be deemed to be a waiver or release of the same, such

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waiver or release to be effected  only  through a written  document  executed by
Payee and then only to the  extent  specifically  recited  therein.  A waiver or
release with reference to any one event shall not be construed as continuing, as
a bar to, or as a waiver or release of, any subsequent right, remedy or recourse
as to a subsequent event.

         8.  Notices.  Except as otherwise  provided  for herein,  any notice or
demand which, by the provisions  hereof, is required or which may be given to or
served upon Maker or Payee shall be in writing  and,  if by  telecopy,  shall be
deemed to have been validly served,  given or delivered when  transmitted with a
copy  immediately  mailed  by  registered  or  certified  mail,  if by  personal
delivery,  shall be deemed to have been validly served,  given or delivered upon
actual  delivery  and, if mailed,  shall be deemed to have been validly  served,
given or delivered  three (3) business  days after  deposit in the United States
mails,  as  registered  or  certified  mail,  with  proper  postage  prepaid and
addressed to the party to be notified, as set forth in the Security Agreement or
to Payee to such other address as Payee shall hereafter give in writing to Maker
by similar notice.

         9.  Successors  and Assigns.  This Note shall be binding upon Maker and
its successors and assigns (including,  without limitation, a receiver,  trustee
or debtor-in-possession of or for Maker) and shall inure to the benefit of Payee
and its  successors  and  assigns.  Maker may not assign  its  rights  hereunder
without the prior written consent of Payee, in its sole  discretion,  other than
by operation of law. Payee may assign all or a part of its interest in this Note
or its rights hereunder to any party without the prior written consent of Maker.

         10.  GOVERNING LAW. THIS NOTE SHALL BE DEEMED A CONTRACT AND INSTRUMENT
MADE  UNDER  THE LAWS OF THE  STATE OF NEW  YORK AND  ACCEPTED  BY PAYEE IN SAID
STATE, AND ANY AND ALL CLAIMS, DEMANDS OR ACTIONS IN ANY WAY RELATING THERETO OR
INVOLVING ANY DISPUTE  BETWEEN ANY OF THE PARTIES TO THIS NOTE,  WHETHER ARISING
IN CONTRACT OR TORT,  AT LAW, IN EQUITY OR  STATUTORILY,  SHALL BE CONSTRUED AND
ENFORCED IN ACCORDANCE WITH AND/OR GOVERNED BY THE LAWS OF THE STATE OF NEW YORK
(EXCEPTING  ITS CHOICE OF LAW RULES,  OTHER  THAN  SECTION  5-1401 OF NEW YORK'S
GENERAL OBLIGATION LAW) AND THE LAWS OF THE UNITED STATES OF AMERICA.

         11.  Severability.  If any  provisions  of this  Note  or any  payments
pursuant to the terms  hereof shall be invalid or  unenforceable  to any extent,
the  remainder  of this  Note and any  other  payments  hereunder  shall  not be
affected  thereby and shall be enforceable to the greatest  extent  permitted by
law.  Furthermore,  in lieu of such invalid or unenforceable  provisions,  there
shall be added  automatically as part of this Note, a provision or provisions as
similar in its or their terms to such invalid or unenforceable provisions as may
be possible and be legal, valid and enforceable.

         12. No Oral Agreements. This Note and the Security Agreement as written
represent  the final  agreement  between  Maker and Payee  with  respect  to the
matters  contained herein and therein and may not be contradicted by evidence of
prior,  contemporaneous  or subsequent oral agreements  between Maker and Payee.
There are no unwritten agreements between Maker and Payee.

         13.  Prepayments.  This  Note  may not be  prepaid  in whole or in part
without  the  consent  of the  holder  hereof and then only if all the Notes are
simultaneously prepaid pro rata.

ZESIGER [14.  Other  Agreements.  This Note shall not constitute a waiver of the
Payee's rights, Maker's obligations or the conditions, if any, contained in that
certain Note Purchase Agreement,  Intercreditor and Collateral Agency Agreement,
Security Agreement,  Pledge Agreement,  Guaranty Agreement and Escrow Agreement,
all of which are dated as of November 29, 2000.]

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UIC [14 Other Agreements. This Note shall not constitute a waiver of the Payee's
rights,  Maker's  obligations or the conditions  contained in that certain Stock
Purchase  Agreement (the "Stock Purchase  Agreement") dated as February 2, 2001,
by and between Maker and the Payee with respect to the Third Tranche  Investment
(as defined  therein) and that certain  Additional  Right to Purchase  Agreement
dated as of February 2, 2001, by and between Maker and the Payee.  The principal
amount of this Note, together with accrued interest,  shall offset the amount of
the  investment  required  by the  Payee  in  Maker  under  the  Stock  Purchase
Agreement,  irrespective  of the  repayment  in full of this Note by Maker.  For
purposes of clarity,  irrespective  of conversion  pursuant to Section 3 of this
Note or payment  pursuant  to Section 1 of this Note,  the amount of  investment
required by the Payee under the Stock Purchase  Agreement is hereby decreased by
the principal amount of this Note, together with accrued interest.  In addition,
the parties hereto hereby agree and acknowledge  that any  participation  by the
Payee in the  Qualified  Equity  Financing  shall also  offset the amount of the
investment  required by the Payee in Maker under the Stock  Purchase  Agreement,
irrespective of the type of security being issued.]

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         IN WITNESS  WHEREOF,  Maker has executed and delivered  this Note as of
the date and year first above written.

                                     MAKER:


                                     PROBEX CORP.,
                                     a Delaware corporation


                                     By:_________________________________
                                     Name: ______________________________
                                     Title: _____________________________




















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