Blower wheel and clamp replacement. Initially, we replaced both the belt and drum roller wheels but that did not stop the noise. By reviewing videos on YouTube and AppliancePartsPros, we suspected that the blower wheel could be problematic, even though with front panel of dryer off, we did not see any visual clues to support that theory. Purchased the replacement clamp as well, just for good measure (and it was inexpensive). Note: we did call AppliancePartsPros with our model AND serial numbers before placing order, because we noticed there were 2 diameters available for the shaft and we did not want to risk purchasing the wrong part. Toughest parts to the job are (a) reseating the drum on the drum rollers, and (b) maneuvering the belt in place around the pulley, as you have to do this by touch, since you cannot see it. We are delighted with the results.