2009 Allison 2500PTS, School Bus, Transmission Assys, Fits to: Thomas Built Saf-T-Liner HDX, (Used) 2008 Allison, TRANSMISSION ASSEMBLY- Model: 2500PTS, Serial Number: 6310871106, Engine: Mercedes OM904LA, 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# 6310871106, Casting# 6310871106, Truck Year 2009 1T7YN4A2291113955