I have a 2020 Chevy HC 2500 diesel. Mine makes the same clunking noise. When the ignition is in acc mode, you can move the steering wheel back and forth and it clunks. No power going to it at all. I’ve been working with two different truck stores and the dealer. The custom truck shops believe it is a bad steering box. This has been a problem for 11,000 miles. I’m sick of it. I live in a rural area and the roads are bumpy. You can feel the clunk all the time. When you turn slightly left or right, it doesn’t do it. Only when going straight. I have a dealer appointment next week.
