2006 Silverado 1500 rear end noise

My 2006 Silverado 1500 crew cab has been making a grinding noise while it is in motion moving forward. The rear brakes(im suspecting the brakes) had been making a clicking sound when I would let my foot off of the brake pedal so I took the drums off on both sides to inspect but did not find anything. After I put everything back together and started driving it it started making a grinding noise anytime after that while in drive moving forward. I don’t think the grinding noise is coming from the brakes as I have took them apart and cleaned everything up already twice as well as adjusted them. Any ideas what this might be?