SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* Onex Partners GP Inc. (Last) (First) (Middle) 712 FIFTH AVENUE 40TH FLOOR (Street) NEW YORK NY 10019 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol Allison Transmission Holdings Inc [ ALSN ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 04/25/2014
	4. 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 Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	04/25/2014		S		12,500,000	D	$29.78	22,821,249	I	See Footnotes(1)(2)(3)(4)

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

1. Name and Address of Reporting Person* Onex Partners GP Inc. (Last) (First) (Middle) 712 FIFTH AVENUE 40TH FLOOR (Street) NEW YORK NY 10019 (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* 1597257 Ontario Inc. (Last) (First) (Middle) C/O ONEX CORPORATION 161 BAY STREET (Street) TORONTO A6 M5J 2S1 (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* New PCo II Investments, Ltd. (Last) (First) (Middle) C/O ONEX CORPORATION 161 BAY STREET (Street) TORONTO A6 M5J 2S1 (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* Onex Partners II GP LP (Last) (First) (Middle) 712 FIFTH AVENUE 40TH FLOOR (Street) NEW YORK NY 10019 (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* Onex Allison Co-Invest LP (Last) (First) (Middle) 712 FIFTH AVENUE 40TH FLOOR (Street) NEW YORK NY 10019 (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* ONEX PARTNERS II L P (Last) (First) (Middle) 712 FIFTH AVENUE 40TH FLOOR (Street) NEW YORK NY 10019 (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* Onex US Principals LP (Last) (First) (Middle) 421 LEADER STREET (Street) MARION OH 43302 (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. Following the reported transaction, includes: (i) 10,317,281 shares of common stock held by Onex Partners II LP; (ii) 6,936,237 shares of common stock held by Onex Allison Holding Limited S.a R.L.; (iii) 4,863,545 shares of common stock held by Onex Allison Co-Invest LP; (iv) 194,367 shares of common stock held by Onex US Principals LP; and (v) 96,971 shares of common stock held by Onex Partners II GP LP.

2. Onex Corporation may be deemed to beneficially own the common stock held by (a) Onex Partners II LP, through Onex Corporation's ownership of all of the common stock of Onex Partners GP Inc., the general partner of Onex Partners II GP LP, the general partner of Onex Partners II LP; (b) Onex Allison Holding Limited S.a R.L., through Onex Corporation's ownership of all of the equity of Onex American Holdings II LLC, which owns all of the equity of each of Allison Executive Investco LLC, which owns all of the equity of Allison Executive Investco II LLC, and Onex American Holdings Subco LLC, which owns all of the equity interests of OAH Wind LLC, which OAH Wind LLC and Allison Executive Investco II LLC own all of the equity interests of Onex Allison Holding Limited S.a R.L.; (continued)

3. (c) Onex Allison Co-Invest LP, through Onex Corporation's ownership of all of the common stock of Onex Partners GP Inc., the general partner of Onex Partners II GP LP, the general partner of Onex Allison Co-Invest LP; (d) Onex US Principals LP, through Onex Corporation's ownership of all of the equity of Onex American Holdings II LLC, which owns all of the equity of Onex American Holdings GP LLC, the general partner of Onex US Principals LP; and (e) Onex Partners II GP LP, through Onex Corporation's ownership of all of the common stock of Onex Partners GP Inc., the general partner of Onex Partners II GP LP.

4. New PCo II Investments Ltd. is the record holder of 411,663 shares of common stock and 1,185 shares of non-voting common stock. 1597257 Ontario Inc., the sole shareholder of New PCo II Investments Ltd., is an independent entity that is controlled by Mr. Gerald W. Schwartz. Mr. Schwartz, the Chairman, President and Chief Executive Officer of Onex Corporation, owns shares representing a majority of the voting rights of the shares of Onex Corporation and as such may be deemed to beneficially own all of the common stock owned beneficially by Onex Corporation. Mr. Schwartz disclaims any such beneficial ownership. Mr. Schwartz has indirect voting and investment control of Onex Corporation.

Remarks:

Due to the limitations of the electronic filing system, Onex Corporation, Gerald W. Schwartz, Onex American Holdings II LLC, Onex American Holdings GP LLC, Allison Executive Investco LLC, Allison Executive Investco II LLC, Onex American Holdings Subco LLC, OAH Wind LLC and Onex Allison Holding Limited S.a R.L. are filing a separate Form 4.

	ONEX PARTNERS GP INC., By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	ONEX US PRINCIPALS LP, By: /s/ Donald F. West, Authorized Person	04/28/2014
	ONEX PARTNERS II GP LP, By: Onex Partners GP Inc., its general partner, By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	ONEX ALLISON CO-INVEST LP, By: Onex Partners II GP LP, its general partner, By: Onex Partners Manager LP, its Agent, By: Onex Partners Manager GP ULC, its general partner, By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	ONEX PARTNERS II LP, By Onex Partners II GP LP, its general partner, By Onex Partners Manager LP, its Agent, By Onex Partners Manager GP ULC, its general partner, By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	1597257 ONTARIO INC., By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	NEW PCO II INVESTMENTS LTD., By: /s/ Andrea E. Daly, Authorized Person	04/28/2014
	** Signature of Reporting Person	Date
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