Measurements of the excess molar enthalpy H-m(E) and the excess molar volume V-m(E) of {xC(4)H(10)) + (1-x)SF6} made in the supercritical region at the pressure p = 8.00 MPa and seven temperatures over the range 311.25-425.75 K are reported. The measurements extend the range of similar measurements made at the pressure 6.00 MPa reported recently. The measurements were made using a flow mixing calorimeter followed by a vibrating tube densimeter. The results are compared with the Patel-Teja (PT) equation-of-state with parameters determined by solving a cubic equation as they recommend, and also with parameters determined by the method suggested by Valderrama-Cisternas (VC) who proposed equations in which the parameters are a function of the critical compressibility factor Z(c). The overall fit to the H-m(E) and V-m(E) measurements obtained using the Valderrama and Cisternas equation is found to be better than that obtained using the parameters obtained by the method suggested by Patel and Teja.