Product review (5 stars): DIY dryer repair for WED9050XW0
This was exactly what WED9050XW0 (Whirlpool) needed. .  The old pulley wheel was obviously very worn, causing the whole unit to scream.  The new wheel 3388672 came with a new triangle washer and circular washer.  When used with four wheels W10314173, and a new belt 661570, the dryer sounded like it did when it was new; extremely quiet.