What does the 2014 chevy silverado engine code p06dd mean?

Code p06dd in a 2014 Chevy Silverado means the engine oil pump has detected a fault in pressures. This can mean a few things. There may be an oil leak, likely from one of the seals, which is allowing air and oil to seep out. This will lower the overall pressure. The oil itself could be low or need to be changed, which is simple enough to do. Finally, the oil pump may not be working right. All of these will lead to the engine not performing as it should in the short term, and if ignored can lead to engine damage over time. The price to fix this issue will change based on the cause, but You should take the car in right away in any case.