washboarding on 2004 Saturn Vue

Has a washboard feel ,seems to be around second and third gear . It'sautomatic and fluid is fine. Feels more like engine cutting out a little . .
Noticed around 45 it wants to rev up and down a little even with steady foot on pedel . Help

Asked by for the 2004 Saturn Vue
I think that your trans is slipping or shuddering. At 45 mph, the torque converter clutch is kicking in and out and this is a problem. I would see a good transmission shop.