OMB APPROVAL

UNITED STATES

OMB Number: 3235-0145

SECURITIES AND EXCHANGE COMMISSION

Expires: February 28, 2009

Washington, D.C. 20549

Estimated average burden hours per response…11

x

Rule 13d-1(b)

o

Rule 13d-1(c)

o

Rule 13d-1(d)

CUSIP No. 320841109

1.

Names of Reporting Persons
I.R.S. Identification No. of Above Persons (Entities Only)
The TCW Group, Inc., on behalf of the TCW Business Unit

2.

Check the Appropriate Box if a Member of a Group*

(a)

o

(b)

x

3.

SEC Use Only

4.

Citizenship or Place of Organization
Nevada corporation

Number of
Shares
Beneficially
Owned by
Each
Reporting
Person With

5.

Sole Voting Power
-0-

6.

Shared Voting Power
2,871,936 (see notes to Item 4)

7.

Sole Dispositive Power
-0-

8.

Shared Dispositive Power
2,871,936 (see notes to Item 4)

9.

Aggregate Amount Beneficially Owned by Each Reporting Person
2,871,936 (see notes to Item 4)

10.

Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*  o

11.

Percent of Class Represented by Amount in Row (9)
9.9%(see response to Item 4)

12.

Type of Reporting Person*(See Instructions)
HC/CO

Item 1

(a).

Name of Issuer:
Wuhan General Group (China), Inc.

Item 1

(b).

Address of Issuer’s Principal Executive Offices:
Canglong Science Park of Wuhan East
Lake Hi-Tech
Development Zone
Wuhan, Hubei, People’s Republic of China
430200

Item 2

(a).

Name of Persons Filing:

Item 2

(b).

Address of Principal Business Office, or if none, Residence:

Item 2

(c).

Citizenship:
The TCW Group, Inc., on behalf of the TCW Business Unit
865 South Figueroa Street
Los Angeles, CA 90017
(a Nevada Corporation)

Item 2

(d).

Title of Class of Securities:
Common Stock

Item 2

(e).

CUSIP Number:
982569105

Item 3.

If this statement is filed pursuant to §§240.13d-1(b), or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

o

Broker or dealer registered under section 15 of the Exchange Act (15 U.S.C. 78o).

(b)

o

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)

o

Insurance company as defined in section 3(a)(19) of the Exchange Act (15 U.S.C. 78c).

(d)

o

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8).

(e)

o

An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E).

(f)

o

An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F).

(g)

x

A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G).
(see Item 7)

The TCW Group, Inc., on behalf of the TCW Business Unit

(h)

o

A savings association as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

o

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

o

Group, in accordance with § 240.13d-1(b)(1)(ii)(J).

Item 4.

Ownership **

The TCW Group, Inc., on behalf of the Business Unit ***

(a)

Amount beneficially owned:   

2,871,936 ****

(b)

Percent of class:   

9.9% ****

(c)

Number of shares as to which such person has:

(i)

Sole power to vote or to direct the vote:

none.

(ii)

Shared power to vote or to direct the vote:

2,871,936 ****

(iii)

Sole power to dispose or to direct the disposition of:

none.

(iv)

Shared power to dispose or to direct the disposition of:

2,871,936 ****

Item 5.

Ownership of Five Percent or Less of a Class.

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following.   N/A

Item 6.

Ownership of More than Five Percent on Behalf of Another Person.

Various persons other than as described in Item 4 have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the Common Units of Rio Vista Energy Partners L.P.

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company.

See Exhibit A.

Item 8.

Identification and Classification of Members of the Group.

Not applicable. See Exhibit A.

Item 9.

Notice of Dissolution of Group.

Not applicable.

Item 10.

Certification.

Because this statement is filed pursuant to Rule 13d-1(b), the following certification is included:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

The TCW Group, Inc., on behalf of the
TCW Business Unit

By:

/s/ Linda D. Barker

Linda D. Barker
Authorized Signatory

(i)

Trust Company of the West, a California corporation and a bank as defined in Section 3(a)(6) of the Securities Exchange Act of 1934.

(ii)

TCW Asset Management Company, a California corporation and an Investment Adviser registered under Section 203 of the Investment Advisers Act of 1940.

(iii)

TCW Investment Management Company, a California corporation and an Investment Adviser registered under Section 203 of the Investment Advisers Act of 1940.