The Case IH 131858R1 is a genuine OEM pinion designed for robust power transmission in a wide range of Case IH agricultural tractors. This critical component ensures proper gear engagement and smooth operation within the drivetrain. Manufactured to original specifications, it provides durability and precise fitment for models including the 430, 440, 450, 460, 560, 660, 706, 756, 766, 806, 826, 856, 966, 1026, 1066, 1206, 1256, 1456, 1466, 1468, 1566, 1568, 2400, 2500, 2606, 2656, 2706, 2756, 2806, 2826, 2856, 3088, 3288, 3388, 3488, 3588, 3688, 3788, 4100, 4156, 4166, 4186, 4366, 4386, 4568, 4586, 4786, 5088, 5288, 5488, 6388, 6588, 6788, 7288, 7488, HYDRO 100, HYDRO 186, HYDRO 70, and HYDRO 86. Refer to your machine's parts catalog for exact compatibility.