Exhibit 99.1

Allison Transmission Announces First Quarter 2022 Results

INDIANAPOLIS, April 27, 2022 – Allison Transmission Holdings Inc. (NYSE: ALSN), a leading designer and manufacturer of propulsion solutions for commercial and defense vehicles and the largest global manufacturer of medium- and heavy-duty fully automatic transmissions, today reported net sales for the first quarter of $677 million, a 15 percent increase from the same period in 2021 and the strongest revenue quarter since 2019, as production continues to accelerate to meet resilient customer demand, and is further driven by the continued execution of Allison’s growth initiatives.

David S. Graziosi, Chairman and Chief Executive Officer of Allison Transmission commented, “Following a notable year in 2021, first quarter 2022 results continue to demonstrate momentum for Allison’s growth objectives. Net sales accelerated into the first quarter, producing the third strongest revenue quarter in Allison’s history, including record quarterly revenue in the Outside North America On-Highway end market. The Allison team continues to deliver solid execution and strong performance, despite persistent global supply chain challenges.”

Graziosi continued, “We are affirming the full year 2022 guidance ranges released to the market on February 16. During the first quarter, we further settled $81 million of share repurchases, or over 2% of outstanding shares, and increased the quarterly dividend for the third consecutive year, from $0.19 to $0.21 per share. In February, the Board of Directors approved a $1 billion increase to the stock repurchase authorization, bringing the total amount authorized under the program to $4 billion. Allison’s disciplined, prudent and well-defined approach to capital allocation continues to drive substantial per share returns while simultaneously facilitating investments across all of our end markets.”

First Quarter Financial Highlights

Net sales for the quarter were $677 million. Year over year results were led by:

Net income for the quarter was $129 million. Diluted EPS for the quarter was $1.30. Adjusted EBITDA, a non-GAAP financial measure, for the quarter was $244 million. Net cash provided by operating activities for the quarter was $163 million. Adjusted free cash flow, a non-GAAP financial measure, for the quarter was $143 million.

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First Quarter Net Sales by End Market

First Quarter Financial Results

Gross profit for the quarter was $320 million, an increase of 10 percent from $291 million for the same period in 2021. The increase in gross profit was principally driven by higher net sales and price increases on certain products partially offset by unfavorable material costs and higher manufacturing expense commensurate with increased net sales.

Selling, general and administrative expenses for the quarter were $75 million, an increase of $2 million from $73 million for the same period in 2021.

Engineering – research and development expenses for the quarter were $43 million, an increase of $5 million from $38 million for the same period in 2021. The increase was principally driven by increased product initiatives spending.

Net income for the quarter was $129 million, an increase of $9 million from $120 million for the same period in 2021. The increase was principally driven by higher gross profit partially offset by a $15 million unrealized loss on marketable securities.

Net cash provided by operating activities was $163 million, an increase of $32 million from $131 million for the same period in 2021. The increase was principally driven by lower operating working capital funding requirements and higher gross profit partially offset by higher cash incentive compensation payments and higher cash interest payments.

First Quarter Non-GAAP Financial Measures

Adjusted EBITDA for the quarter was $244 million, an increase of $22 million from $222 million for the same period in 2021. The increase in Adjusted EBITDA was principally driven by higher gross profit partially offset by increased product initiatives spending.

Adjusted free cash flow for the quarter was $143 million, an increase of $36 million from $107 million for the same period in 2021. The increase was driven by higher net cash provided by operating activities and lower capital expenditures.

Full Year 2022 Guidance Update

We are affirming the full year 2022 guidance ranges released to the market on February 16. Allison expects 2022 Net Sales in the range of $2,625 to $2,775 million, Net Income in the range of $430 to $520 million, Adjusted EBITDA in the range of $865 to $975 million, Net Cash Provided by Operating Activities in the range of $570 to $680 million, Adjusted Free Cash Flow in the range of $400 to $500 million and Capital Expenditures in the range of $170 to $180 million.

Our 2022 net sales guidance reflects higher demand in the Global On-Highway, Global Off-Highway and Service Parts, Support Equipment & Other end markets as a result of the ongoing global economic recovery, continued strength in customer demand and price increases on certain products.

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Conference Call and Webcast

The company will host a conference call at 5:00 p.m. ET on Wednesday, April 27 to discuss its first quarter 2022 results. The dial-in phone number for the conference call is 1-877-425-9470 and the international dial-in number is 1-201-389-0878. A live webcast of the conference call will also be available online at http://ir.allisontransmission.com.

For those unable to participate in the conference call, a replay will be available from 8:00 p.m. ET on April 27 until 11:59 p.m. ET on May 4. The replay dial-in phone number is 1-844-512-2921 and the international replay dial-in number is 1-412-317-6671. The replay passcode is 13728348.

About Allison Transmission

Allison Transmission (NYSE: ALSN) is a leading designer and manufacturer of propulsion solutions for commercial and defense vehicles and the largest global manufacturer of medium- and heavy-duty fully automatic transmissions that Improve the Way the World Works. Allison products are used in a wide variety of applications, including on-highway trucks (distribution, refuse, construction, fire and emergency), buses (school, transit and coach), motorhomes, off-highway vehicles and equipment (energy, mining and construction applications) and defense vehicles (tactical wheeled and tracked). Founded in 1915, the company is headquartered in Indianapolis, Indiana, USA. With a presence in more than 150 countries, Allison has regional headquarters in the Netherlands, China and Brazil, manufacturing facilities in the USA, Hungary and India, as well as global engineering resources, including electrification engineering centers in Indianapolis, Indiana, Auburn Hills, Michigan and London in the United Kingdom. Allison also has more than 1,400 independent distributor and dealer locations worldwide. For more information, visit allisontransmission.com.

Forward-Looking Statements

This press release contains forward-looking statements. All statements other than statements of historical fact contained in this press release are forward-looking statements, including all statements regarding future financial results. In some cases, you can identify forward-looking statements by terminology such as “may,” “will,” “should,” “expect,” “plans,” “project,” “anticipate,” “believe,” “estimate,” “predict,” “intend,” “forecast,” “could,” “potential,” “continue” or the negative of these terms or other similar terms or phrases. Forward-looking statements are not guarantees of future performance and involve known and unknown risks. Factors which may cause the actual results to differ materially from those anticipated at the time the forward-looking statements are made include, but are not limited to: the duration and spread of the COVID-19 pandemic, including new variants of the virus and the pace and availability of vaccines and boosters, mitigating efforts deployed by government agencies and the public at large, and the overall impact from such outbreak on economic conditions, financial market volatility and our business, including but not limited to the operations of our manufacturing and other facilities, the availability of labor, our supply chain, our distribution processes and demand for our products and the corresponding impacts to our net sales and cash flow; increases in cost, disruption of supply or shortage of labor, freight, raw materials or components used to manufacture or transport our products or those of our customers or suppliers, including as a result of the war in Ukraine and the COVID-19 pandemic; our participation in markets that are competitive; our ability to prepare for, respond to and successfully achieve our objectives relating to technological and market developments, competitive threats and changing customer needs, including with respect to electric hybrid and fully electric commercial vehicles; the highly cyclical industries in which certain of our end users operate; uncertainty in the global regulatory and business environments in which we operate; the concentration of our net sales in our top five customers and the loss of any one of these; the failure of markets outside North America to increase adoption of fully automatic transmissions; the success of our research and development efforts, the outcome of which is uncertain; U.S. and foreign defense spending; risks associated with our international operations, including acts of war and increased trade protectionism; general economic and industry conditions; the discovery of defects in our products, resulting in delays in new model launches, recall campaigns and/or increased warranty costs and reduction in future sales or damage to our brand and reputation; our ability to identify, consummate and effectively integrate acquisitions and collaborations; labor strikes, work stoppages or similar labor disputes, which could significantly disrupt our operations or those of our principal customers or suppliers; risks related to our indebtedness; and other risks and uncertainties associated with our business described in our Annual Report on Form 10-K. Although we believe the expectations reflected in such forward-looking statements are based upon reasonable assumptions, we can give no assurance that the expectations will be attained or that any deviation will not be material. All information is as of the date of this press release, and we undertake no obligation to update any forward-looking statement to conform the statement to actual results or changes in expectations.

Use of Non-GAAP Financial Measures

This press release contains information about Allison’s financial results and forward-looking estimates of financial results which are not presented in accordance with accounting principles generally accepted in the United States

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(“GAAP”). Such non-GAAP financial measures are reconciled to their closest GAAP financial measures at the end of this press release. Non-GAAP financial measures should not be considered in isolation or as a substitute for our reported results prepared in accordance with GAAP and, as calculated, may not be comparable to other similarly titled measures of other companies.

We use Adjusted EBITDA and Adjusted EBITDA as a percent of net sales to measure our operating profitability. We believe that Adjusted EBITDA and Adjusted EBITDA as a percent of net sales provide management, investors and creditors with useful measures of the operational results of our business and increase the period-to-period comparability of our operating profitability and comparability with other companies. Adjusted EBITDA as a percent of net sales is also used in the calculation of management’s incentive compensation program. The most directly comparable GAAP measure to Adjusted EBITDA is Net income. The most directly comparable GAAP measure to Adjusted EBITDA as a percent of net sales is Net Income as a percent of net sales. Adjusted EBITDA is calculated as the earnings before interest expense, net, income tax expense, amortization of intangible assets, depreciation of property, plant and equipment and other adjustments as defined by Allison Transmission, Inc.’s, the Company’s wholly-owned subsidiary, Second Amended and Restated Credit Agreement. Adjusted EBITDA as a percent of net sales is calculated as Adjusted EBITDA divided by net sales.

We use Adjusted Free Cash Flow to evaluate the amount of cash generated by our business that, after the capital investment needed to maintain and grow our business and certain mandatory debt service requirements, can be used for the repayment of debt, stockholder distributions and strategic opportunities, including investing in our business. We believe that Adjusted Free Cash Flow enhances the understanding of the cash flows of our business for management, investors and creditors. Adjusted Free Cash Flow is also used in the calculation of management’s incentive compensation program. The most directly comparable GAAP measure to Adjusted Free Cash Flow is Net cash provided by operating activities. Adjusted Free Cash Flow is calculated as Net cash provided by operating activities, after additions of long-lived assets.

Attachments

Contacts

Raymond Posadas

Managing Director, Investor Relations

ir@allisontransmission.com

(317) 242-3078

Media Relations

media@allisontransmission.com

(317) 242-5000

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Allison Transmission Holdings, Inc.

Condensed Consolidated Statements of Operations

(Unaudited, dollars in millions, except per share data)

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Allison Transmission Holdings, Inc.

Condensed Consolidated Balance Sheets

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Allison Transmission Holdings, Inc.

Condensed Consolidated Statements of Cash Flows

(Unaudited, dollars in millions)

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Allison Transmission Holdings, Inc.

Reconciliation of GAAP to Non-GAAP Financial Measures

(Unaudited, dollars in millions)

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Allison Transmission Holdings, Inc.

Reconciliation of GAAP to Non-GAAP Financial Measures for Full Year Guidance

(Unaudited, dollars in millions)

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