Here you go man a list of all the GM t-bars part numbers and max torques:

CHEVY TORSION BAR CODES AND RATINGS:

15048307-LH (code XK) (Max torque 4553)
15048308-RH (code XK) (Max torque 4553)

15048309-LH (code XL) (Max torque 4626)
15048310-RH (code XL) (Max torque 4626)

15712407-LH (code WX) (Max torque 4863)
15712408-RH (code WX) (Max torque 4863)

15048311-LH (code XM) (Max torque 5638)
15048312-RH (code XM) (Max torque 5638)

15058267-LH (code YH) (Max torque 5913)
15058268-RH (code YH) (Max torque 5913)

15712409-LH (code WY) (Max torque 5913)
15712410-RH (code WY) (Max torque 5913)

15528957-LH (code GG) (Max torque 6709)
15528958-RH (code GG) (Max torque 6709)

15712411-LH (code WZ) (Max torque 7267)
15712412-RH (code WZ) (Max torque 7267)

15528963-LH (code GK) (Max torque 8615)
15528964-RH (code GK) (Max torque 8615)

15528965-LH (code GL) (Max torque 8782)
15528966-RH (code GL) (Max torque 8782)

15732338-LH (code XG) (Max torque 9054)
15732339-RH (code XG) (Max torque 9054)

15528959-LH (code GH) (Max torque 7161)
15528960-RH (code GH) (Max torque 7161)