2012 MDX Shudders at different speeds

Hello, my gut feeling is that you could have some vibration from the torque converter of the transmission. Have you serviced your fluid lately? It should be served every time the "minder 3" indicator comes on, which is every 30,000 - 40,000 miles. If you tow, you should do it promptly every 30,000 miles, at least. The fluid breaking down can reduce the performance of the torque converter. Doing 3 drain and fills of the transmission will refresh most of the fluid (you cannot drain all the fluid, just 3-4 quarts at a time). Drive the vehicle a bit in between transmission services to circulate new and old fluid. This is merely a guess; diagnostic tools can capture and record torque converter performance and confirm this as the root cause if it's indeed the case. In some extreme cases, the converter will need to be replaced.

Have experienced mechanic test drive vehicle.