Tap here to read more about Deck Pulley Tensioner Arm for John Deere X320 X340 48 M157175 M157176. Premium Quality Replacement Part. Deck Pulley w/Tensioner Arm. X340 48 (SN: 085001 -). X500 – 54 (SN: 030001 -). X520 X534 X540 – 54 (SN: 030001 -). 1 x Pulley : M157175. Width : 14.35mm – 0.56 in. Inner Diameter : 16.03mm – 0.63 in. Outer Diameter : 137mm – 5.39 in. Hole Distance : 67mm – 2.6 in. 1 x Pulley : M157176. Width : 25.6mm – 0.98in. Inner Diameter : 16mm – 0.62in. Outer Diameter : 165mm – 6.49in. 1 x Tensioner Arm : AM137197. Width : 45.3mm – 1.78in. Length : 186.8mm – 7.35in. Central Hole Diameter : 20mm – 0.78in.