HEI, or Hilliard Enterprises, Inc., is a leading supplier of locomotive parts and services, based in North Little Rock, Arkansas. Established in the late 1980s by Chip Hilliard, the company has grown to become one of the largest used and remanufactured locomotive parts dealers in the nation and worldwide. HEI specializes in providing EMD, G.

E., and ALCO diesel engines and spare parts to domestic and international locomotive, marine propulsion, and power generation industries. They offer a wide selection of quality locomotive components to customers across the world, including Class I railroads, short-line railroads, independent operators, parts dealers, and rebuilders. In addition to parts, HEI also offers locomotive services and inspections in some regions of the US.

With over 100 years of combined experience, the senior staff at HEI is dedicated to delivering competitively priced, high-quality parts and service to support their clients' needs. The company maintains a large inventory of parts and has rapid access to even hard-to-find and obsolete items. HEI invites both existing and potential customers to visit their facilities and learn more about the quality of their services