Scotty, I got a 2014 GMC Sierra 1500 with the 6.2L engine. It’s 4wd and has roughly 97,000 miles. Last week I had a valve spring break and replaced that. The problems just keep coming though. Now I have a grinding sound that appears to be coming directly under my feet. 99% of the time it happens at low rpm, and when on a slight incline. Like when the transmission is right on the verge of downshifting, but hasn’t decided to and it putting a little bit of a load on the engine by staying in a gear higher, but still needing a little extra power to keep speed going up the incline. It also does it when taking off slowly from a stop, same thing, low rpm driving. It stops as soon as I let off the gas pedal, or if I really lay the pedal down. It clearly has to be driveline related. It doesn’t seem to be AFM related, and I do not have the flapper valve on the exhaust, I removed that long ago. But for the life of me I can’t figure it out. This is in just regular old 2wd mode by the way. If you have heard of this issue before, or know what to look at it would be great. Any help is incredibly appreciated!!