I have a 2011 Endeavor and hear a constant whistling noise that seems to be coming from the upper rear windshield only when going above 65mph on the highway. The rear window seals appear to be in good condition. Does anyone have a fix for this issue? The driveshaft was replaced by the previous owner 20k miles ago. Thanks

 

Have you considered it could be a rear wheel bearing? I had a humming sound that was resolved by replacing the wheel bearing assembly.