2011 Allison 2500PTS, School Bus, Transmission Assys, Fits to: Thomas Built Saf-T-Liner HDX, (Used) 2010 Allison (AT), TRANSMISSION ASSEMBLY- Model: 2500PTS, Serial Number: 6310992117, 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# 6310992117, Casting# 6310992117, Truck Year 2011 1T7YN4E25B1137943