**Exhibit 99.6**

**CERTIFICATION PURSUANT TO RULE 13a-14 OR 15d-14 OF THE SECURITIESEXCHANGE ACT OF 1934**

I,Todd Takeyasu, certify that:

1.               I have reviewed this annual report on Form40-F of Penn West Energy Trust;

2.               Based on my knowledge, this report does notcontain any untrue statement of a material fact or omit to state a materialfact necessary to make the statements made, in light of the circumstances underwhich such statements were made, not misleading with respect to the periodcovered by this report;

3.               Based on my knowledge, the financialstatements, and other financial information included in this report, fairlypresent in all material respects the financial condition, results of operationsand cash flows of the issuer as of, and for, the periods presented in thisreport;

4.               The issuer’s other certifying officer and Iare responsible for establishing and maintaining disclosure controls andprocedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) for theissuer and have:

(a)          Designed such disclosure controls andprocedures, or caused such disclosure controls and procedures to be designedunder our supervision, to ensure that material information relating to theissuer, including its consolidated subsidiaries, is made known to us by otherswithin those entities, particularly during the period in which this report isbeing prepared;

(b)         Evaluated the effectiveness of the issuer’sdisclosure controls and procedures and presented in this report our conclusionsabout the effectiveness of the disclosure controls and procedures, as of theend of the period covered by this report based on such evaluation; and

(c)          Disclosed in this report any change in theissuer’s internal control over financial reporting that occurred during theperiod covered by the annual report that has materially affected, or isreasonably likely to materially affect, the issuer’s internal control overfinancial reporting; and

5.               The issuer’s other certifying officer and Ihave disclosed, based on our most recent evaluation of internal control overfinancial reporting, to the issuer’s auditors and the audit committee of theissuer’s board of directors (or persons performing the equivalent function):

(a)          All significant deficiencies and material weaknesses in the design oroperation of internal control over financial reporting which are reasonablylikely to adversely affect the issuer’s ability to record, process, summarizeand report financial information; and

(b)         Any fraud, whether or not material, thatinvolves management or other employees who have a significant role in theissuer’s internal control over financial reporting.
| Dated:  March 26, 2007 |                                                                               |
|-----------------------------|------------------------------------------------------------------------------------|
|                        |                                                                               |
|                        | /s/ Todd Takeyasu                                                                  |
|                        | Todd Takeyasu                                                                      |
|                        | Senior Vice President and and Chief Financial  Officer of Penn West Petroleum Ltd. |

 

----