How to Replace 8547174 Dryer Idler Pulley Arm on Whirlpool & Maytag Dryers — Step-by-Step

Your Whirlpool WED6400SW1 is making a grinding noise that gets louder with every load, or the drum won't spin at all even though the motor runs. Nine times out of ten, that's your idler pulley arm failing. The wheel wears out, the arm cracks, and suddenly your dryer's belt tension system collapses.

This repair looks intimidating because you've got to access the inside of the cabinet, but it's actually one of the more straightforward fixes. The 8547174 pulley arm assembly comes with the wheel already mounted, so you're not fighting with tiny parts. Let's get your dryer quiet again.

What You Need Before Starting

• 1/4-inch nut driver or socket set
• Flathead screwdriver
• Work gloves (that drum can get sharp)
• Putty knife or paint scraper
• Towel or cardboard to protect your floor

Time Required: 30-45 minutes
Difficulty: Moderate — requires accessing dryer cabinet and handling belt tension

Safety First

Unplug your dryer completely. If it's gas, turn off the gas supply valve and disconnect the gas line — you'll need to move the unit away from the wall. Electric dryers just need the power cord unplugged. Wait 10 minutes before starting to let any residual charge dissipate. The drum edge can be surprisingly sharp, so keep your hands positioned carefully when reaching inside.

Step 1: Remove the Front Panel to Access the Drum

Open the dryer door and locate two screws inside the door opening at the top — one on each side. Remove these with your 1/4-inch driver. Next, slide a putty knife between the top panel and front panel about 3 inches from each corner to release the spring clips. Lift the top up and prop it against the wall. Now you can lift the front panel up and off — it hooks at the bottom, so tilt it forward once the top clips are free.

Step 2: Release Belt Tension and Remove the Drum

With the front off, you'll see the drum, belt, and your failed idler pulley down at the bottom right. Reach underneath the drum and locate the idler pulley — it's spring-loaded. Push the entire idler arm toward the motor to create slack in the belt, then slip the belt off the motor pulley. You can now lift the drum straight out. It's heavy and awkward, so use both hands and watch that back edge.

Step 3: Remove the Failed Idler Pulley Assembly

The idler pulley arm mounts to a bracket with a single bolt or nut. On most Whirlpool models like the WGD6200SW2 or WED6600VU0, it's a 1/4-inch hex head bolt. Remove this fastener and the entire arm assembly comes off. Check the mounting bracket for cracks while you're here — if it's damaged, you'll need to address that too or your new pulley won't last.

Step 4: Install the New 8547174 Pulley Arm

Position your new pulley arm on the mounting bracket. The wheel should point toward where the drum will sit, and the spring hook should face the motor. Thread the bolt back in and tighten it snug — not gorilla-tight, just firm. Give the wheel a spin with your finger. It should rotate freely without wobbling. If it binds or feels rough, loosen the bolt slightly and reposition the arm.

Step 5: Reinstall the Belt and Drum

Loop the dryer belt around the drum with the grooved side against the drum. Lower the drum back into the cabinet, then reach underneath and route the belt around the idler pulley wheel and then around the motor pulley. Push the idler arm toward the motor to create slack, position the belt on the motor pulley, then release. The spring tension will snap everything into place. Manually rotate the drum a few times — it should turn smoothly with even resistance.

Step 6: Reassemble and Test

Set the front panel back on — bottom hooks first, then press the top clips into place. Replace those two screws inside the door opening. Lower the top panel and make sure the spring clips catch. Plug the dryer back in (or reconnect gas and restore gas supply). Run a 10-minute test cycle with no clothes. Listen for that grinding noise — it should be completely gone. The drum should spin quietly with just the normal hum of the motor and airflow.

Testing After Installation

Run a full drying cycle with a medium load of towels. Listen during the entire cycle for any unusual noises. A properly tensioned belt with a good idler pulley should be nearly silent except for the blower. Check that the drum stops immediately when you open the door — that's your door switch working, but it confirms the belt and pulley system is functioning correctly. If you hear squeaking, the belt might be slightly misaligned on one of the pulleys.

Frequently Asked Questions

How do I know if my idler pulley is bad or if it's the motor pulley?

The idler pulley typically makes noise constantly during the cycle, while a bad motor pulley often squeals only when the drum first starts moving. If your dryer won't spin at all but the motor runs, that's almost always the idler pulley — the arm breaks and the belt goes slack. Remove the front panel and manually check both pulleys. The idler wheel should spin freely and feel smooth. If it's rough, notched, or doesn't spin, it's failed.

Can I just replace the wheel, or do I need the whole arm assembly?

The 8547174 comes as a complete assembly with the wheel already mounted on the arm. While some older models had replaceable wheels, these Whirlpool and Maytag units use a riveted or pressed-on design. Trying to replace just the wheel usually results in improper tension or alignment. For $28.99, the complete assembly is worth it for the reliability and correct fit.

Will this fix a dryer that takes forever to dry clothes?

Only if the drum isn't spinning properly. A failing idler pulley can cause the belt to slip, which means the drum turns slowly or intermittently. That'll definitely make drying take longer. But if your drum spins fine and drying is just slow, you're looking at airflow issues — clogged vent, bad heating element, or failed thermostat. Fix the pulley first if it's noisy or the drum speed seems inconsistent, then tackle airflow if needed.