Product review (3 stars): Works, but needs some adjustment, plus tips on how to remove and install
Same part number as the old that broke(nice job on durability, Whirlpool) on our 1.5 year old Whirlpool dishwasher.  Wheels that came with the new part are considerably  smaller then the original.  So if your wheels are smaller, BEFORE you install this part, cut off the new wheels on the new assembly carefully using a pair of side/wire cutters (don't cut the supporting tabs that lock the wheel on).  Then install your original larger wheels, which simply push on.  There are 3 pieces of plastic on the mechanism  that must be removed to install this new assembly.  One on each end, which requires you to slide the piece to where it can fit over and off  plastic tabs (be patient, look and be gentle) and a center piece, that requires gently pinching in the central tabs and popping it inwards. Then turn the dish rack upside down and pull the large  plastic cover on the adjustment section outward enough to allow you to wiggle and pull the old assembly out.  When installing the new piece, again pull the cover outward towards you and guide the assembly in. Note that the adjustment levers fit IN BETWEEN  the guides on the new assembly when installing.  Then reinstall the 3  plastic pieces that were removed above, using the opposite  side as a guide as to how they fit if needed.  Much cheaper then having a repairman come out and isn't covered by our extended warranty, as it is not considered a "mechanical part".  Truly a sad commentary on the durability of new versus old appliances...