It just started recently

2005 Nissan frontier

Noise starts at ~2100 RPMs and increase pitch after 2800 RPM noise quiets. there are days when there is no sound. I removed the serpentine belt and the noise is gone. Thoughts??

Have pics. I thought the drive sounded just a tiny bit off then next day drove 50 miles and when came to slow drive I could hear metal rub on and off. Then more so after stop to look at it. More when turn left but getting worse and perhaps cause it's getting colder at night
Maybe I dried things out when washed truck and sprayed inner wheels

6 Cylinder ,4 .0 V crew cab

the idle seems too high too, like 1.5 rpms, the tranny downshifts inappropriately. It is not equipped with the automatic hill downshift feature.... ive only had it for 1 week and if it always sounds like a tightly wound rubber band, its embarassing and i dont want to keep it. Is it filters and bands? Is it suppose to sounds so...1980 economy car?

Need to remove and install starter on 05 nissan frontier 4 wheel drive would like to know how long it takes