Whirlpool Dishwasher Spray Arm Replacement — What This Part Does
The upper and lower spray arms distribute wash water across the dishes during each cycle. Water flows through the feed tube and pumps out of the spray holes, causing the arm to rotate. When arms become clogged with food debris, hard-water scale, or broken glass, or when the plastic cracks, warps, or loses its mounting integrity, water cannot reach dishes evenly and cleaning performance drops.
Common failure modes include spray holes blocked by mineral buildup, arms that will not spin freely due to worn retaining nuts or bushings, and cracked or warped plastic from years of heat and detergent exposure. Poor loading or worn mounting hardware can also prevent the arm from turning. If cleaning the holes does not restore free rotation and proper spray patterns, you need to replace the arm and any damaged mounting parts.
Signs It Needs Replacing
- Dishes on top or bottom rack come out dirty or still have food residue One rack cleans poorly because the corresponding spray arm is not distributing water evenly.
- Spray arm does not spin freely when turned by hand Worn mounting hardware, a damaged retaining nut, or debris inside the arm prevents smooth rotation.
- Visible cracks, warping, or missing pieces on the spray arm Heat and detergent over time can cause the plastic to crack or warp, reducing spray pressure and coverage.
- Spray holes are clogged with white mineral deposits or food debris Hard-water scale or lodged particles block the holes and prevent water from reaching dishes.
- Arm wobbles, sits too high, or rubs against the rack or tub Worn bushings, washers, or feed-tube mounting points cause misalignment and noise during operation.
- Retaining nut or mounting clip is loose, cracked, or missing Without secure hardware the arm shifts out of position and cannot spin properly.
How to Replace It
- Disconnect power at the breaker or unplug the dishwasher, then turn off the water supply valve under the sink.
- For lower spray arm replacement, pull out the lower rack, locate the retaining nut or collar at the center hub, and rotate it counterclockwise to unlock and lift the arm off the mounting post.
- Inspect the spray holes for clogs and check the mounting hub and retaining nut for cracks or wear; if cleaning does not restore free rotation, proceed with a new arm.
- For upper spray arm replacement, remove the upper rack from the tub, locate the water supply tube connection and mounting bracket, disconnect the tube if needed, and pull the old arm assembly free.
- Align the new spray arm onto the mounting hub or feed tube, pressing firmly until it seats or snaps into place, then rotate the retaining nut clockwise (lower arm) or reconnect the bracket (upper arm) to lock it down.
- Spin the arm by hand to confirm it turns freely without rubbing the rack, tub walls, or other components.
- Reinstall the rack, restore water and power, and run a short rinse cycle to verify the arm rotates and water sprays evenly through all holes.
- Check for leaks at the feed-tube connection (upper arm) and confirm dishes on both racks receive full water coverage during the wash cycle.
The Part You Need
| Part | Notes |
|---|---|
| Whirlpool dishwasher lower spray arm | Amazon | Part numbers W10837249 and W10340527 fit many Whirlpool models; find your exact number on the model and serial plate inside the door frame or tub edge. |
| Whirlpool dishwasher upper spray arm assembly | Amazon | May include feed tube, mounting bracket, and clips; verify fitment using the full model number from the rating plate. |
| Spray arm retaining nut, bushing, or mounting hardware kit | Amazon | Replace if worn or cracked during disassembly; often sold separately or with the arm. |
Related Error Codes
If this part is failing you may also see one of these codes:
- Whirlpool Dishwasher E1 error code
- Whirlpool Dishwasher E15 error code
- Whirlpool Dishwasher E3 error code
- Whirlpool Dishwasher E4 error code
- Whirlpool Dishwasher E6 error code
- Whirlpool Dishwasher E7 error code
- Whirlpool Dishwasher F10E5 error code
- Whirlpool Dishwasher F1E1 error code
- Whirlpool Dishwasher F2E2 error code
- Whirlpool Dishwasher F3E1 error code
When to Call a Pro
If you cannot remove the spray arm due to seized hardware, if the feed tube or mounting bracket inside the tub is cracked and requires disassembly of internal components, or if replacing the arm does not restore cleaning performance and you suspect pump, circulation, or valve issues, call a qualified appliance technician. Pros have the tools to diagnose water-flow problems, test the wash motor and pump assembly, and access parts deep inside the tub without risk of further damage.