How to Clean a Dishwasher (Filter, Spray Arms, Smell)

A dishwasher that smells like sour milk almost always traces back to one part: the manual filter at the bottom of the tub. Bosch, Whirlpool, and GE all build current models with a filter that traps food and does not clean itself. The steps below come straight from those three brands’ own support pages, plus habits confirmed by Consumer Reports and real owner reviews. Every guide on The Practical Choice is built from published specs, certification databases, and named third-party sources; see how we score for the full method.

How to Clean the Dishwasher Filter (Bosch, Whirlpool, GE)

The core steps are the same across brands, with small differences in how the filter twists loose.

1. Remove the bottom rack. On most machines the filter sits in a back corner or around the base of the lower spray arm.
2. Twist the filter loose. Bosch says to twist and pull the filter out with its mesh screen. Whirlpool’s two-part filters need a quarter turn counterclockwise on the upper assembly, then the lower filter lifts forward. GE’s Ultra Fine Filter twists counterclockwise; the Fine Filter underneath comes out by turning its two retaining posts counterclockwise.
3. Rinse under running water and work a soft brush or old toothbrush into the mesh. All three brands warn against wire brushes or scouring pads, which tear the mesh.
4. For caked-on starch or grease, soak the parts 10 to 15 minutes in warm water with a little dish soap before brushing again.
5. Reinstall in reverse order and turn each part clockwise until it locks. On Whirlpool models with a “Clean Filter” light, hold the reset button 3 seconds with the filter back in place, then open and close the door.

The three brands do not agree on how often to do this, so follow your own brand’s number. Bosch’s support page says the filter “needs to be cleaned regularly to avoid overflow” but does not publish an exact interval (Bosch owner support). Whirlpool sets a range of every 3 to 6 months depending on use and pre-rinsing (Whirlpool product help). GE is the most specific: clean the filters every other month, sooner if dishes feel gritty (GE Appliances support). Consumer Reports splits the difference at every couple of months, per testing lead Larry Ciufo (Consumer Reports).

How to Clean the Spray Arms

A clogged spray arm hole looks like a weak or uneven wash even after the filter is spotless.

1. Lift the bottom spray arm off its post, or twist and pull the top arm free, depending on your model.
2. Hold each arm up to a light and check the small holes along its length for trapped grit.
3. Push a toothpick through each hole from the inside toward the outside, so debris comes out the way it went in rather than packing deeper.
4. For mineral scale from hard water, soak the arm 30 minutes in warm water with a half cup of white vinegar, then scrub the holes with an old toothbrush.
5. Rinse, snap the arm back onto its post, and spin it by hand to confirm it turns freely before closing the door.

Whirlpool treats the spray arms as part of general interior upkeep, not a separate job: its product help site says residue builds up on “internal components like spray arms” and recommends a monthly affresh tablet on an empty cycle, or 2 cups of white vinegar in a cup on the top rack, used sparingly since vinegar’s acidity can damage seals over time (Whirlpool product help).

Why a Dishwasher Still Smells After You Clean It

According to Larry Ciufo, who leads dishwasher testing at Consumer Reports, a clogged manual filter is the single most common cause of dishwasher odor, and it also makes the machine wash less effectively (Consumer Reports). Consumer Reports adds two steps people skip: wiping the rubber door seal, where residue and mold collect, and running a monthly citric-acid cleaner such as Affresh or Finish through an empty cycle (Consumer Reports).

Owner reviews back this up. On ConsumerAffairs’ GE Dishwashers page, 727 reviews averaging 1.4 out of 5 as of this writing, one reviewer wrote: “Also have to clean the filter at least every two days.” (ConsumerAffairs, GE Dishwashers reviews, Jul 2025) Another said: “We have cleaned filters and spray out the bottom of the washer. Never worked so hard on a dishwasher that doesn’t clean dishes or glasses.” (ConsumerAffairs, GE Dishwashers reviews, Jul 2025) ConsumerAffairs skews toward frustrated owners, so read the 1.4 average as a ceiling on how bad things get, not a typical score, but the filter and odor complaints match what the brands’ own manuals warn about.

A sanitize cycle will not fix a dirty filter. Dishwashers certified to NSF/ANSI 184 must hit a 150 degree Fahrenheit final rinse and cut bacteria by 99.999 percent on that cycle, but the standard measures disinfecting performance, not whether food sitting in an unwashed filter still smells (NSF).

Common Mistakes That Make a Dishwasher Dirty or Smelly

• Running small, half-empty loads. Owner reviews of Whirlpool front-control dishwashers describe odor building up when rinsed dishes sit inside for a couple of days waiting for a full load.
• Assuming any filter is self-cleaning. If you can twist a part loose by hand, it is a manual filter and needs the steps above.
• Overloading the racks so dishes block the spray arms. Water that cannot reach a plate redeposits food on other dishes and clogs the filter faster.
• Using vinegar every single wash. Whirlpool calls vinegar an acid that can damage the machine with frequent use, and recommends it only occasionally.
• Ignoring the door gasket. Consumer Reports lists the rubber seal as a separate wipe-down step because a normal cycle does not rinse it.

When to Stop Cleaning and Start Shopping

Cleaning fixes odor and weak washing caused by buildup, but it will not fix a worn-out machine. Sears Home Services, an appliance repair provider, uses a simple threshold: if a repair estimate runs 50 percent or more of the cost of a new dishwasher, replacement is usually the better value (Sears Home Services). That threshold matters more once a machine passes the 8 to 12 year range most repair technicians treat as a typical service life. If you clean the filter on schedule and the machine still leaves grit on glasses, will not drain, or smells within days of a full clean, the fix is probably mechanical, not a maintenance gap. The Best Dishwashers of 2026 uses the same published-spec, certification-first method to compare current models.

FAQ

How often should I clean my dishwasher filter?

Follow your brand’s own number: Whirlpool says every 3 to 6 months, GE says every other month, and Consumer Reports recommends checking every couple of months regardless of brand. Clean it sooner any time dishes come out gritty or the tub smells (Whirlpool product help; GE Appliances support; Consumer Reports).

Why does my dishwasher still smell after I clean the filter?

Check the rubber door seal next. Consumer Reports lists it as a separate residue trap that a normal wash cycle does not rinse, and recommends wiping it with a rag along with a monthly citric-acid cleaner cycle (Consumer Reports).

Can I run vinegar through my dishwasher every load?

No. Whirlpool’s own product help site describes vinegar as acidic and warns that frequent use can damage internal components, recommending it as an occasional treatment rather than a routine step (Whirlpool product help).

Does a sanitize cycle replace filter cleaning?

No. A sanitize cycle certified to NSF/ANSI 184 has to hit a 150 degree Fahrenheit final rinse and a 99.999 percent bacteria reduction, but that standard tests the cycle’s disinfecting performance, not whether a clogged filter still holds rotting food (NSF).

How do I know if my spray arm holes are clogged instead of the filter?

Pull the spray arm off and hold it up to a light. If several holes look blocked even after the filter is clean, clear them with a toothpick pushed from the inside out, then soak the arm in warm water with white vinegar if hard water scale is the cause.