2013 Allison 2500PTS, School Bus, Transmission Assys, Fits to: Thomas Built Saf-T-Liner HDX, (Used) 2013 Allison (AT), TRANSMISSION ASSEMBLY- Model: 2500PTS, Serial Number: 6311129768, Engine: Cummins ISL, Reference images for condition, For more information about this item, give us a call. We ship Worldwide! (CRG HEAVY TRUCK PARTS) 929 W PULASKI HWY, ELKTON MD 21921, Serial# 6311129768, Casting# 6311129768, Truck Year 2013 1T7YN4E29D1157938