Finally got an answer.
I found this site w/ google search. Lousy design to adjust PB on 2009.
Got to remove the wheel and rotor to adjust it. The PB equalizer does nothing. I tried it twice. This was a 'Certified' Impala bought in 2009 w/6000 miles on it. Sticker was checked off to note that everything was OK and checked. Baloney. The BP was loose then and is now. The Vehicle was bought in Phoenix and garaged in Cottonwood (100 miles North) I found a busted stud in RR wheel. Dealer claimed it is not covered under warrrenty!
Changed his mind when I paged Chevy Customer Service and the BBB. Thie is a BtoB warrenty but the stud is not covered???
Doesn't say that in the owners manual.
To adjust PB.........