The EMD GP8 is a model of four-axle diesel locomotive rebuilt by Illinois Central's Paducah shops using a General Motors Electro-Motive Division (EMD) GP7, GMD GP7 or GP9 as a start.

Core units used in the construction of these units were Illinois Central GP7, GP9, a GP8, C&O GP9, D&RGW GP9, DT&I GP7, N&W GP7, P&LE GP7, QNS&L GP7, RDG GP7, St.J&LC GP9, SLSF GP7, and SP GP9.

Rock Island's Silvis Shops rebuilt 20 Conrail GP7s into GP8s in 1978.

Morrison-Knudsen's Boise Shops rebuilt 13 Conrail GP7s into GP8s in 1978.

The 1976 Conrail units rebuilt at Paducah were the equivalent of the Illinois Central rebuilds.