We examine the fully developed flow of a generalized fluid of second g
rade between heated parallel plates, due to a pressure gradient along
the plate. The constant coefficient of shear viscosity of a fluid of s
econd grade is replaced by a shear dependent viscosity with an exponen
t m. If the normal stress coefficients are set equal to zero, this mod
el reduces to the standard power-law model. We obtain the solution for
the case when the temperature changes only in the direction normal to
the plates for the two most commonly used viscosity models, i.e. (i)
when the viscosity does not depend on temperature, and (ii) when the v
iscosity is an exponentially decaying function of temperature.