X0306 4 2019-02-20 0001411207 Allison Transmission Holdings Inc ALSN 0001661939 Pittard Dana JH ONE ALLISON WAY INDIANAPOLIS IN 46222 0 1 0 0 VP, Defense Programs Employee Stock Option (right to buy) 49.60 2019-02-20 4 A 0 5905 0 A 2029-02-20 Common Stock 5905 5905 D Restricted Stock Units 2019-02-20 4 A 0 1968 0 A Common Stock 1968 1968 D Performance Stock Units 2019-02-20 4 A 0 6410 0 A Common Stock 6410 6410 D The option vests on February 20, 2022. Each restricted stock unit ("RSU") represents a contingent right to receive one share of Allison Transmission Holdings, Inc. common stock. The RSUs vest on February 20, 2022. Each performance-based restricted stock unit ("PSUs") represents a contingent right to receive one share of Allison Transmission Holdings, Inc. common stock. On February 17, 2016, the reporting person was granted PSUs with the number of PSUs earned to be determined based on the extent to which certain performance conditions were met for a performance period of 2016-2018. As determined on February 20, 2019, based on the Company's actual performance for 2016-2018, the reporting person earned 6,410 PSUs. Earned PSUs will vest on February 28, 2019. /s/ Jacalyn C. Bolles, attorney-in-fact 2019-02-22