Possible vacuum leak high frequency squeel

Hey all, just joined today and was wondering if anyone one else has had this issue. I have an 09 Tacoma Quad cab 4x4 and I get a high frequency squeal/hum noise that will only occur when I am cornering over 50km. The noise goes away when I straighten up or just touch the brake. The local Toyota shop can't figure it out but suspects its vacuum related. Anyone else have this issue?

 

Anti-sway bar? Those usually klunk, but notoriously while cornering (or speed bumps). Easy enough to eliminate as the source anyway.

Welcome to TW. Good luck with the cure.

 

no its not a clunking sound. its a whistle hum sound, very low frequency.