Catalysis of the transfer of a solute or solutes from one side of a membrane to the other according to the reaction: succinate(out) + fumarate(in) = succinate(in) + fumarate(out).
Catalysis of the transfer of a solute or solutes from one side of a membrane to the other according to the reaction: succinate(out) + fumarate(in) = succinate(in) + fumarate(out).