Exhibit

4..3




 




SECOND

AMENDMENT TO LOAN AGREEMENT




 




 




THIS SECOND AMENDMENT TO LOAN AGREEMENT (the “First Amendment”) is entered into as of the 3rd day of July, 2002, by and between PIONEER DRILLING

COMPANY, a Texas corporation,

formerly known as South Texas Drilling & Exploration, Inc. (“Borrower”), and THE FROST NATIONAL BANK, a

national banking association (“Lender”) and this amendment is joined

in  by PIONEER DRILLING SERVICES, LTD.,

a Texas limited partnership, formerly known

as Pioneer Drilling Co., Ltd.,  (“Pioneer”).




 




R E C I T A L S




 




A.            On

August 11, 2000, Borrower and Lender entered into that certain Loan Agreement

(as amended, the “Agreement”) concerning the terms, conditions and

covenants of certain Credit Facilities.




 




B.            Borrower

has requested and Lender has agreed to consent to Borrower’s sale of certain

subordinated debentures.




 




C.            All

capitalized terms not otherwise defined in this First Amendment shall have the

same meanings as are set forth in the Agreement.




 




NOW, THEREFORE, for 

and in consideration of the mutual covenants and promises herein

contained, Lender and Borrower agree as follows:




 




AGREEMENTS




 




1.             Section

8, subsection (e) is deleted in its entirety and the following is substituted

in its place:




 




(e)           Indebtedness.  Create,

incur or assume any indebtedness for borrowed money or issue or assume any

other note, debenture, bond or other evidences of indebtedness, or guarantee

any such indebtedness or such evidences of indebtedness of others, (or permit

Pioneer to do so) other than (i) borrowings from Lender,

(ii) borrowings from lenders other than Lender, except that during the

term of the Loan, Borrower and Pioneer (in the aggregate) shall be permitted to

incur or have outstanding indebtedness to other lenders provided that the aggregate

principal balance of all such debt outstanding at any time shall not exceed

$5,000,000.00 (exclusive of the subordinated debt in the total amount of

$28,000,000.00 described in that certain Subordination Agreement as of July 3,

2002 (the “Convertible Subordinated Debentures”) and (iii) the

Convertible Subordinated Debentures.




 





























 




2.             Except

as specifically modified or amended herein, all terms, provisions and

requirements of the Agreement shall remain as written, and as amended from time

to time.  Borrower hereby reaffirms all

covenants, conditions, representations and warranties contained in the

Agreement, as amended by this First Amendment.




 




IN WITNESS WHEREOF, the parties

hereto have caused this First Amendment to be duly executed as of the date

first above written.




 




	

  BORROWER:


  	

   


  	

  LENDER:


  
	

   


  	

   


  	

   


  
	

  PIONEER DRILLING COMPANY, a Texas corporation, formerly known as South

  Texas Drilling & Exploration, Inc.,  a Texas corporation (executing for purposes of

  joining in  certain

  specific provisions, as noted above)


  	

   


  	

  THE FROST NATIONAL BANK


  a national banking association 


  
	

   


  	

   


  
	

   


  	

  By:


  	

   


  
	

   


  	

  Printed

  Name: 


  	

   


  
	

   


  	

  Title:


  	

   


  
	

   


  	

   


  	

   


  
	

  By:

  


  	

   


  	

   


  	

   


  
	

  Printed

  Name:


  	

   


  	

   


  	

   


  
	

  Title:


  	

   


  	

   


  	

   


  
	

   


  	

   


  	

   


  
	

   


  	

   


  	

   


  
	

  AGREED TO:


  	

   


  	

   


  
	

   


  	

   


  	

   


  
	

  PIONEER DRILLING SERVICES, LTD., a Texas

  limited partnership formerly known as Pioneer

  Drilling Co., Ltd., a Texas limited

  partnership


  	

   


  	

   


  
	

   


  	

   


  	

   


  
	

  By:


  	

  PDC Mgmt. Co., a Texas

  corporation,


  General Partner


  	

   


  	

   


  
	

   


  	

   


  	

   


  
	

   


  	

  By:  


  	

   


  	

   


  	

   


  
	

   


  	

  Printed

  Name:


  	

   


  	

   


  	

   


  
	

   


  	

  Title:


  	

   


  	

   


  	

   


  
																





 




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