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Replacement parts for General Electric GLD5960N00SS Dishwasher | AppliancePartsPros.com

Check that the arm's supply tube fits correctly to the supply tube at the back of the unit.

Could be a fill problem so the arm is starving for water.
This can be easily checked by adding a couple quarts of hot water after a fill to see if the arm now works OK. Just be careful that you do not overfill it. Most units fill to just under the heating element.
If it is low fill the most likely cause is the screen filter on the input side of the fill valve. Remove the valve and check/clean the screen. Do not permanently remove it as it is there to keep crud out of the valve which could hold it open and cayuse a flood.

Remove the sump cover (Item 506 in Section 1) and check the sump (Item 508 in Section 1) for debris/grime etc. Be careful as there is often broken glass in the sump.

Check/clean the main filter (Item 451 in Section 4).

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