SEC Form 3

FORM 3

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 INITIAL STATEMENT OF BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940

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1. Name and Address of Reporting Person* TCG HOLDINGS LLC (Last) (First) (Middle) C/O THE CARLYLE GROUP 1001 PENNSYLVANIA AVE. NW, SUITE 220S (Street) WASHINGTON DC 20004 (City) (State) (Zip)	2. Date of Event Requiring Statement (Month/Day/Year) 03/14/2012	3. Issuer Name and Ticker or Trading Symbol Allison Transmission Holdings Inc [ ALSN ]
		4. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)	5. If Amendment, Date of Original Filed (Month/Day/Year)
			6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Beneficially Owned
1. Title of Security (Instr. 4)	2. Amount of Securities Beneficially Owned (Instr. 4)	3. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	4. Nature of Indirect Beneficial Ownership (Instr. 5)
Common Stock	90,356,250	I	See footnote(1)

Table II - Derivative Securities Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 4)	2. Date Exercisable and Expiration Date (Month/Day/Year)		3. Title and Amount of Securities Underlying Derivative Security (Instr. 4)		4. Conversion or Exercise Price of Derivative Security	5. Ownership Form: Direct (D) or Indirect (I) (Instr. 5)	6. Nature of Indirect Beneficial Ownership (Instr. 5)
	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* TCG HOLDINGS LLC (Last) (First) (Middle) C/O THE CARLYLE GROUP 1001 PENNSYLVANIA AVE. NW, SUITE 220S (Street) WASHINGTON DC 20004 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TC Group, LLC (Last) (First) (Middle) C/O THE CARLYLE GROUP 1001 PENNSYLVANIA AVE. NW, SUITE 220S (Street) WASHINGTON DC 20004 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* TC Group IV Managing GP, L.L.C. (Last) (First) (Middle) C/O THE CARLYLE GROUP 1001 PENNSYLVANIA AVE. NW, SUITE 220S (Street) WASHINGTON DC 20004 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Carlyle Partners IV AT Holdings, L.P. (Last) (First) (Middle) C/O THE CARLYLE GROUP 1001 PENNSYLVANIA AVE. NW, SUITE 220S (Street) WASHINGTON DC 20004 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. By Carlyle Partners IV AT Holdings, L.P. TC Group IV Managing GP, L.L.C. is the general partner of Carlyle Partners IV AT Holdings, L.P. TC Group, L.L.C. is the managing member of TC Group IV Managing GP, L.L.C. TCG Holdings, L.L.C. is the managing member of TC Group, L.L.C. Accordingly, each of TC Group IV Managing GP, L.L.C., TC Group, L.L.C. and TCG Holdings, L.L.C. may be deemed to be beneficial owners of shares of common stock owned of record by Carlyle Partners IV AT Holdings, L.P. TCG Holdings, L.L.C. is managed by a three-person managing board, and all board action relating to the voting or disposition of these shares requires approval of a majority of the board. William E. Conway, Jr., Daniel A. D'Aniello and David M. Rubenstein, as the managing members of TCG Holdings, L.L.C., may be deemed to share beneficial ownership of shares of common stock beneficially owned by TCG Holdings, L.L.C. Such individuals expressly disclaim any such beneficial ownership.

Remarks:

Exhibit List: Exhibit 24 - Confirming Statement Exhibit 99 - Joint Filer Information

	/s/ Jeremy W. Anderson, attorney-in-fact	03/14/2012
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 5 (b)(v).
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