Block M (mass of 15.65 kg)

is initially moving to the left with a speed of 3.77 m/s. The mass of m is 8.26 kg and the coefficients of friction are Us = 0.411 and Uk = 0.304. The string is massless and the pulley is
massless and frictionless. How fast will M be traveling when m has fallen through a height h = 2.47 meters?

W=change in E
This is what I have done:
1/2Mvf^2-1/2Mvi^2+1/2mvf^2-1/2mvi^2-mgh-UkMg=0
I then solved for for vf. The answer is suppose to be 4.62 but I am way off. I need help fixing my set up.