squeek or winning noise at 2500 rpm

Hello all I need some HELP!

I just got my self a new 2010 toyota tacoma 2.7 4x4 with 12000miles and love it. But After I had my first oil change "I told them 5-20" I started to notice and winning nose at 2200 to 3000 rpm. But only when I'm driving. I cant get it to do it in my drive way so I can find it. Since I normaly cruise at about that range on the freeway or streets its driving me crazy. Does any one know if this is normal? I have only had this truck for three weeks now and dont know whats a normal sound or a bad sound or if it has always been there? any help thanks!

 

Ya I dont wan to take it to the dealer if I dont half to. It happens and all speeds in any gear as long as your as 2500rpm and giving either 1/4 to 1/2 throttle. there no real vibration i have noticed.