280 SLC Coupe R107 06/1976 - 09/1981 M110.982,986. 280 SE W116 09/1976 - 07/1980 M110.985. 280 SEL W116 08/1976 - 07/1980 M110.985. 280 E W123 02/1976 - 11/1985 M110.98. This is probably because of modern fuel additives & the introduction of ethanol into fuel.
