X0407 4 2023-05-03 1 0001411207 Allison Transmission Holdings Inc ALSN 0001367016 Reynolds Richard VanFleet C/O ALLISON TRANSMISSION HOLDINGS, INC. ONE ALLISON WAY INDIANAPOLIS IN 46222 1 0 0 0 0 Common Stock 2023-05-03 4 M 0 37044 0 A 37044 D Deferred Stock Units 2023-05-03 4 M 0 4068 0 D Common Stock 4068 0 D Dividend Equivalent Rights 2023-05-03 4 M 0 3523 0 D Common Stock 3523 0 D Deferred Stock Units 2023-05-03 4 M 0 3466 0 D Common Stock 3466 0 D Deferred Stock Units 2023-05-03 4 M 0 3162 0 D Common Stock 3162 0 D Deferred Stock Units 2023-05-03 4 M 0 3628 0 D Common Stock 3628 0 D Deferred Stock Units 2023-05-03 4 M 0 3185 0 D Common Stock 3185 0 D Deferred Stock Units 2023-05-03 4 M 0 2859 0 D Common Stock 2859 0 D Deferred Stock Units 2023-05-03 4 M 0 2880 0 D Common Stock 2880 0 D Deferred Stock Units 2023-05-03 4 M 0 3600 0 D Common Stock 3600 0 D Deferred Stock Units 2023-05-03 4 M 0 2927 0 D Common Stock 2927 0 D Deferred Stock Units 2023-05-03 4 M 0 3746 0 D Common Stock 3746 0 D Represents the deferred stock units ("DSUs") and dividend equivalents payable upon the reporting person's separation from service. The reporting person did not stand for re-election at Allison Transmission Holdings, Inc.'s (the "Company") 2023 annual meeting of stockholders and his term ended on May 3, 2023. Includes 33,521 DSUs and 3,523 related dividend equivalents. Each DSU is the economic equivalent of one share of the Company's common stock. The DSUs become payable, in common stock, or at the Company's election cash, at the earlier of the reporting person's separation from service or a change in control. DSUs earn dividend equivalents when dividends are declared on the Company's common stock. On May 9, 2013, the reporting person was granted 4,068 DSUs that vested on May 8, 2014. Each dividend equivalent right is the economic equivalent of one share of the Company's common stock. The dividend equivalent rights accrued on previously awarded DSUs and were payable on May 3, 2023, the date of the reporting person's separation from service. On May 9, 2014, the reporting person was granted 3,466 DSUs that vested on May 14, 2015. On May 15, 2015, the reporting person was granted 3,162 DSUs that vested on May 12, 2016. On May 13, 2016, the reporting person was granted 3,628 DSUs that vested on May 12, 2017. On May 12, 2017, the reporting person was granted 3,185 DSUs that vested on May 10, 2018. On May 10, 2018, the reporting person was granted 2,859 DSUs that vested on May 9, 2019. On May 9, 2019, the reporting person was granted 2,880 DSUs that vested on May 6, 2020. On May 7, 2020, the reporting person was granted 3,600 DSUs that vested on May 5, 2021. On May 6, 2021, the reporting person was granted 2,927 DSUs that vested on May 4, 2022. On May 5, 2022, the reporting person was granted 3,746 DSUs that vested on May 3, 2023. /s/ Eric C. Scroggins, attorney-in-fact 2023-05-05