Long block 855 Engines (1/2 - 3/4 Assembly) are suitable replacements for existing engines that have experienced catastrophic failure, but the ancillary components are still in good working order. If you spun a bearing, threw a rod through the block or dropped a valve a long block is more cost effective alternative to a more complete option. Check the turbo, fuel pump, manifolds, fuel lines and accessory drive components are undamaged before looking at a long block option. Metal shavings and lack of oil pressure can oftentimes leave unseen damage. Long blocks are a good option for both on-highway and off-highway industrial use. 855 NTC, NTA, NT, NH versions can be built to spec either as an extended long block or long block option to an ESN and CPL Number. Check with your sales representative for lead time and availability for custom engine orders.