Mid range rpm grinding
 

I have a 2004 Volvo s60 2.4 with 174500miles with an automatic transmission, I started noticing at about 160000 miles that if I accelerated up to 4000 rpm and up it would make a grinding noise and start hesitating. It doesn't do it when I do normal city driving without going on the highway. And it doesn't do it in first gear. It happens when I try to get up to speed on upward hills and when I'm trying to pass someone on the highway. If you have any ideas feel free to respond.