Maybe you have the noise but don't realize it?

It takes a very slow and gradual throttle to notice the clunk. If you miss it, you won't hear it again until the next restart at least 5 minutes away.

The tech did say he could hear it from 4.8 as well and said it may be the sound of transfer case teeth biting into the chain or something. And said most people may not notice it because they start the car and go fast in a noisy environment.