Louder engine above 50 mph

Hi,
I have a dodge caravan 2003 V6 3.3 Lt.
Since 1 month, I noticed my engine sound become really louder when I drive above 50 mph. But the engine do not lost any power. Below 50 the sound is just normal. I will really appreciate is someone knows what might be the issue.

Thank you.

change your oil and put a different grade/synthetic oil in. Probably a bearing on the lower end of the motor.

Is the tramsmission shifting into third or overdrive???? Try shifting the transmission manualy mto see if tthre is a difference.