As the the title says, my truck has a vibration when hitting 40 threw 55mph, it’s like I’m driving on rumble strips, if I let off the gas it’ll stop but pick back up. It’s not a constant rumble but happens heavily at those speeds.
Edit/ 2020 Chevy Colorado Z71 V6, automatic trans, does have 4x4 capability, under 50,000 miles
Definitely a torque converter clutch shutter. Super common. Flushing the fluid fixed the earlier models. Should be under powertrain warranty though.