From the 2011 Press Release:
Brake feel and performance are greatly improved with the 2011 Silverado HD trucks. The standard four-wheel disc system is completely revamped to deliver smoother, more immediate and confident-feeling performance. Four-wheel, four-channel ABS is standard on all single-rear-wheel models and a three-channel system is standard on dual-rear-wheel models.
The front and rear rotors are larger in diameter – 14 inches (355 mm) – and width on all models to support their increased capacity, weight ratings and trailering ratings, while the calipers are stiffer and stronger. The hydroboost brake booster calibration is revised for reduced pedal effort and the travel of the pedal is also revised for a more comfortable, confident feel.
Larger wheel hub and bearing assemblies complement the new brake system and the rear rotors attach to the wheel hubs for easier servicing.
Specifically, dually wheels are 17" and SRW's are 18".
Front rotors are 13.97" x 1.57", Rears are 14.17" x 1.34"
For comparison purposes, the 2007 HD rotors are 12.8" x 1.2" front and 12.8" x 1.5" rear.
So yeah, it sounds like your 16's won't carry over.