Exhibit 99

Joint Filer Information


Date of Event Requiring Statement:		March 20, 2012

Issuer Name and Ticker or Trading Symbol:		Allison Transmission Holdings, Inc. [ALSN]

Designated Filer:		TCG Holdings, L.L.C.

Other Joint Filers:		TC Group, L.L.C. TC Group IV Managing GP, L.L.C. Carlyle Partners IV AT Holdings, L.P.
Addresses:		The address of each of the reporting persons is c/o The Carlyle Group, 1001 Pennsylvania Ave., N.W., Suite 220 South, Washington, DC 20004-2505.

Signatures:

Dated: March 22, 2012


		TCG HOLDINGS, L.L.C.
		by:		/s/ Jeremy W. Anderson, attorney-in-fact

		Name:		David M. Rubenstein
		Title:		Managing Director

		TC GROUP, L.L.C. By: TCG Holdings, L.L.C., its Managing Member

		by:		/s/ Jeremy W. Anderson, attorney-in-fact

		Name:		David M. Rubenstein
		Title:		Managing Director

		TC GROUP IV MANAGING GP, L.L.C. By: TC Group, L.L.C., its Managing Member By: TCG Holdings, L.L.C., its Managing Member

		by:		/s/ Jeremy W. Anderson, attorney-in-fact

		Name:		David M. Rubenstein
		Title:		Managing Director

		CARLYLE PARTNERS IV AT HOLDINGS, L.P. By: TC Group IV Managing GP, L.L.C., its General Partner By: TC Group, L.L.C., its Managing Member By: TCG Holdings, L.L.C., its Managing Member

		by:		/s/ Jeremy W. Anderson, attorney-in-fact

		Name:		David M. Rubenstein
		Title:		Managing Director

TCG HOLDINGS LLC 4