X0508 4 2023-08-28 0001411207 Allison Transmission Holdings Inc ALSN 0001918190 van Niekerk Teresa C/O ALLISON TRANSMISSION HOLDINGS, INC. ONE ALLISON WAY INDIANAPOLIS IN 46222 0 1 0 0 VP, Chief Procurement Officer 0 Common Stock 2023-08-28 4 M 0 5705 49.60 A 19614 D Common Stock 2023-08-28 4 M 0 5520 43.13 A 25134 D Common Stock 2023-08-28 4 M 0 3302 39.42 A 28436 D Common Stock 2023-08-28 4 S 0 12153 59.1710 D 16283 D Employee Stock Option (right to buy) 49.60 2023-08-28 4 M 0 5705 0 D 2029-02-20 Common Stock 5705 0 D Employee Stock Option (right to buy) 43.13 2023-08-28 4 M 0 5520 0 D 2031-02-10 Common Stock 5520 2761 D Employee Stock Option (right to buy) 39.42 2023-08-28 4 M 0 3302 0 D 2032-02-23 Common Stock 3302 6605 D The price reported is a weighted average price. These shares were sold in multiple transactions at per share prices ranging from $59.1000 to $59.2200. The reporting person undertakes to provide Allison Transmission Holdings, Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote. The option vested on February 20, 2022. The options vest in three equal annual installments beginning on February 10, 2022. The options vest in three equal annual installments beginning on February 23, 2023. /s/ Preston B. Ray, attorney-in-fact 2023-08-30