2004 Chevy Avalanche Popping Noise

Was it the Intermediate Steering Shaft, thats the only thing that will make a pop noise and can be greased. If it is you can grease it yourself, you can get the kit from the dealer. I would replace it because greasing it is only temporary if you replace it it won't come back, but the I shafts are expensive. Here is the part #19153614
post back with any other info or questions.