I'm assuming you're talking about the middle spray arm (#10 on the upper wash & rinse parts break down diagram
) and the mounting bracket for this spray arm (#5 on the upper wash & rinse parts break down diagram
There should be the four tabs on the mounting bracket and the shaft to attach the spray arm and the manifold together. If any of these parts is broken off - it will never stay in place.
Most likely the mounting bracket has to be replaced.
- The part number for the mounting bracket is AP3081228
If you're talking about the 3rd level spinner (#3 on the upper wash & rinse parts break down diagram
) - the retainer for this spinner consists of two parts and it comes together with the new spinner.
In order to replace it you have to release the locking tabs on the top portion of the feeding tube and carefully pull it down just to reach the top part of the retainer.
- The part number for the 3rd level spinner is AP3177952
Here are the break down diagrams for the Whirlpool dishwasher Model GU1500XTLT0