1981 Mack EM6, Truck Delivery, Engine Assys, Fits to: Mack R686ST, (Used) 1980 Mack EM6-285, ENGINE ASSEMBLY- Displacement: 6.72L, Horsepower: 285, E.C.S.: ASPL, For more information about this item, give us a call. We ship Worldwide! (CRG HEAVY TRUCK PARTS) 929 W PULASKI HWY, ELKTON, MD 21921, Horse Power 285, Serial# TBD, Mileage 0 1M2N178Y7BA069587