You likely need to adjust your draft and position control linkage and I think you can eventually cause bigger problems if you do not. I have installed draft control on several tractors including an MX5100 that is like yours. Get the one page installation sheet and adjust. Easy peasey. You just put a 100 lb weight on the drawbar and adjust the length of the threaded rods a little bit and tighten lock nuts. One must have moved. Instruction should be put there and I have them if you can’t locate. I am out of town for a few more days, however. The tractors I have done,
M7040, MX5100 and
L4300 all had the same instructions. Once you understand and use draft control correctly, you will amaze and amuse your friends with most any ground engaging or grading operation. People stop to take pictures of my work. Good luck.