A fully developed forced convection heat transfer of a thermally independent shear thinning (n=0.75) and Newtonian fluids flowing inside a uniform heated axially pipe has been carried out numerically by means of the large eddy simulation (LES) with an extended Smagorinsky model at a simulation's Reynolds and Prandtl numbers equal to Res=4000 and Prs=1 respectively. The present investigation aims to ascertain the accuracy and reliability of the LES laboratory code predicted results and evaluate the effectiveness of the extended Smagorinsky model to resolve and describe the evolution of the main mean flow quantities and thermal statistics in the present computational domain especially at the wall vicinity. The Computations are based on a finite difference scheme, second order accurate in space and in time, the numeric resolution is 65 3 grid points in r, θ and z direction respectively, with length of the domain of 20R. The predicted results show an excellent agreement with the DNS results, the main findings show that the present LES laboratory code can be considered as a powerful tool for predicting the mean thermal quantities of the Non-Newtonian fluid. The reduction in the fluid flow index (n) results in enhancement in the mean axial velocity and a pronounced attenuation in the mean temperature over the radial direction, where leads also to noticeable drop in the average Nusselt number.