Clothes dryer with its vent duct in a small laundry closet

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Dryer leaves spots, grease marks or dark smudges on clothes

Most dryer stains are product or residue: dryer sheets added to a partly dry load, melted lip balm, crayon or gum left in the drum from an earlier load, or dye transfer from new denim. A machine cause is less common: black smudges along the edge of clothes from worn front drum glides or seals, or rust from a damaged drum. Confirm the stains appear only after drying, then wipe-test the drum.

Cross-checked ~30 min easyBrands: All

Before you start

Unplug the dryer before cleaning inside the drum
Do not use flammable solvents inside a dryer, especially a gas dryer; let any cleaner dry fully and air out before running

Diagnostic steps

Unlock all 4 steps with expected values

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