There is a shimmy or shake between 20 & 30 mph. What causes this?

Hello, Dave here, contributing to RepairPal and providing expert advice since 2010. This is not a terribly common concern, so there's no "for sure" answer without testing. A diagnostic tool can monitor engagement and performance of the shifting as well as the torque converter clutch engagement and disengagement. Often times if the torque converter is shuddering, it can be addressed by draining and filling the transmission fluid 3 times, a good effort to refresh all the transmission fluid -- which can't be done in full at once. Make sure you use Honda DW1 transmission fluid only and recheck operation. If it continues and the diagnostic tool shows the shuddering, you may need work internally. https://repairpal.com/auto-repair-near-me Click the link or call us at 877-913-1554. We'll gladly find you a certified RepairPal shop in your area.