They also need to replace the ISS bearing, which has a plastic race and once the plastic is distorted it clunks.Yep, it is most likely the intermediate steering shaft. Take it back to the dealer and see if they can fix it. Even after replacing the shaft, mine came back, so not all are the steering shaft. Although, there is supposed to be a "new and improved" shaft that came out.
if you cant afford to pay for a new shaft or don't want to open your hood unbolt the steering shaft and push up and pull down a couple of times cycleing the shaft thourgh its range of movement 9 times out of ten will fix the clunck at least for a while relocates the grease in the shaft
NOTE: BE EXTREMELY CAREFULL NOT TO ROTATE THE SHAFT IF MIS-REINSTALLED CAN BREAK THE CLOCK SPRING FOR THE AIRBAG EXPENSIVE REPAIR.