If the motor runs but the drum doesn't turn, or the drum spins with no resistance by hand, the belt has almost certainly broken or slipped off the idler pulley. On most front-panel dryers you unplug it, remove two screws and the front panel, lift the drum enough to feed the new belt around it, then loop it over the idler and motor pulley with the smooth side against the drum.
Signs the belt is the problem
A broken belt has a few telltale symptoms. You press Start, the motor hums or runs, and the drum sits still. Or the dryer won't start at all, because some models have a belt switch that keeps the motor off once the belt snaps. Open the door and turn the drum by hand. With a good belt it takes real effort. With a broken one it spins freely.
A belt that's worn but not broken tends to squeal, thump once per revolution, or slip under a heavy load. LG dryers show LE and Samsung dryers show 3C when the drum or motor isn't turning right. Those codes cover more than the belt, so check it before you buy a motor.
Order the right belt and gather tools
Belts are model-specific. Find the full model number on the label inside the door frame or on the back of the cabinet and order the belt listed for it. Belts that look alike can differ in length, and the wrong one won't tension properly.
If the dryer has a few years on it, look at the idler pulley and drum rollers while you're inside. They're the parts that usually wear alongside the belt, and replacing them now saves taking the dryer apart twice.
- Phillips screwdriver
- 5/16 in (8 mm) nut driver
- Work gloves (sheet metal edges are sharp)
- Flashlight and a shop vacuum for the lint you'll find
- Time: AppliancePartsPros calls it a quick job with the right part; allow extra time for a first attempt
Unplug the dryer and deal with gas dryers carefully
Pull the plug from the wall, or switch off the dryer breaker if you can't reach the outlet. An electric dryer's 240-volt plug is heavy and stiff. Grip the plug body, never the cord.
If you have a gas dryer, leave the gas line exactly as it is. You don't need to shut the valve, disconnect the flexible connector, or touch any gas fitting for this job, and you shouldn't. The belt is reached from the front on most models, so you only need enough room to open the front panel. If your dryer has to be pulled out so far that the gas connector would bend sharply or stretch, stop and have an appliance technician do the move. A strained connector can leak.
If you smell gas at any point, stop work, don't operate switches or plugs, leave the house and call your gas company from outside.
Remove the front panel and bulkhead
Designs vary, so look for a tech sheet tucked inside the cabinet and check your owner's manual. The steps below follow the Whirlpool, KitchenAid and Maytag front-panel layout described in AppliancePartsPros' belt guide. If your dryer is built differently, follow the instructions for your model number.
Disconnect the door switch wiring if the harness won't reach once the panel is off. Snap a phone photo before unplugging any connector.
Remove the two Phillips screws at the lower front corners of the cabinet.
Lift the front panel slightly, swing the bottom out to free it from the top clips, and rest it to one side without pulling on the wires.
Release the wire clip that holds the harness to the bulkhead so the wires can move.
Remove the four 5/16 in screws holding the front bulkhead (two at the top, two at the bottom), lift it off its supports, tilt it forward and set it down.
Support the drum with one hand so it doesn't drop onto the rear rollers or the motor.
Take off the old belt and check the pulleys
Push the idler arm toward the motor to take the tension off, then slip the belt off the motor pulley and the idler. If the belt has already broken, it's lying loose in the bottom of the cabinet. Slide it out from around the drum.
Before the new belt goes on, spin the idler pulley by hand. It should turn smoothly and quietly. A wobble, a gritty feel, or a flat spot means replace it now. Spin each drum roller too. Vacuum the lint out of the bottom of the cabinet while it's open, because that lint is fuel.
Fit the new belt around the drum
Lay the new belt over the drum and seat it in the groove or faint track toward the back where the old belt ran. The smooth side goes against the drum and the ribbed side faces out. iFixit points out that a belt flipped the wrong way can slip and squeal.
Lift the front of the drum back into place on its glides or rollers and let the belt hang down toward the motor. If you need to hold the drum up while you work, prop it with a small box rather than your knee.
Route the belt around the idler and motor pulley
This step trips people up. Reach under the drum and pull the idler arm toward the motor. Pass the belt loop around the idler pulley, then around the motor pulley, so the belt makes a zigzag or S-shape between them. Ease the idler arm back and it should snap the belt tight. If your dryer has a routing diagram on a label inside the cabinet, follow it over any general description, including this one.
Turn the drum by hand two or three full revolutions. The belt should stay centered on the drum and on both pulleys without walking off. If it slips or the idler arm sits slack, the belt is off the idler or routed wrong. Redo it now, before the panels go back on.
Pull the idler arm toward the motor to open a gap.
Loop the belt around the idler pulley.
Loop it around the motor pulley so the idler pushes against the belt.
Let the idler arm go and confirm the belt is tight.
Spin the drum by hand to check tracking.
Reassemble and test
Reverse the teardown: bulkhead on its tabs, four screws, harness clip, door switch connector, front panel hooked onto the top clips, two lower screws. Make sure no wire is pinched between panels.
Plug the dryer in and run an empty timed cycle for 5 to 10 minutes. Listen for squeaking or thumping, and check that the drum stops when you open the door. A slight rubber smell on the first run is normal. A strong burning smell is not, so stop the dryer and recheck the routing.
When to call a professional
Call a technician if the new belt breaks or slips within a few loads, since a seized roller, idler or drum bearing is probably dragging. Also get help if the motor hums but won't turn with the new belt in place, or if a gas dryer needs moving that would put strain on its connector.