2003-2008 Subaru Forester Window Motor: Slow Windows & Gusset Issues

Symptoms of a Failing Power Window Motor

A power window motor rarely fails without warning. Recognizing the early signs can help you diagnose the problem correctly and avoid replacing the wrong parts. The symptoms often overlap with a failing window regulator, but there are clues to tell them apart.

1. Slow Window Operation

This is the most common early symptom of a failing motor in a 2003-2008 Forester. The window will struggle to go up, often moving much slower than it used to. It might get progressively worse over time until it stops moving completely. While this points to a weak motor, it's also a classic sign of another common Forester issue explained below.

2. Window is Completely Dead or Intermittent

If you press the switch and nothing happens at all—no sound, no movement—the motor may have completely failed. It could also be an electrical issue like a blown fuse or a bad switch. If the window works sometimes but not others, it could be a sign of a dead spot in the motor's internal windings or a loose connection.

3. Clicking, Humming, or Grinding Noises

When you press the switch, listen closely to the inside of the door. A faint hum or buzz means the motor is receiving power but is unable to turn, either because it has seized internally or the window is jammed. A series of clicks can also indicate the motor is trying to engage but failing. A loud grinding or crunching sound often points to a problem with the window regulator's gears or cables, rather than the motor itself.

A Critical Related Issue: Worn Window Gussets

On the 2003-2008 (SG) Forester, one of the most common reasons for premature window motor failure is worn-out window gussets. These are the triangular rubber pieces at the front corner of the window where the mirror mounts. Over time, this rubber dries out, tears, and loses its shape. This causes two problems:

• Excessive Wind Noise: The most obvious symptom is a loud rushing or whistling sound from the front windows at highway speeds.
• Increased Drag: More importantly, the deformed gusset no longer guides the glass properly. It creates significant drag, forcing the window motor to work much harder to push the glass up. This constant strain overheats the motor and causes it to weaken and fail over time.

If your window is slow, inspect these gussets. If they are torn or deformed, they should be replaced along with the motor to prevent the new motor from failing prematurely. Replacing the gussets can often restore smooth, fast window operation on its own if the motor isn't too far gone.

How to Diagnose the Problem

Before buying parts, follow these steps to confirm the motor is the culprit.

1. Check the Fuse: This is the simplest first step. Consult your owner's manual for the power window fuse location and check if it's blown.
2. Listen for Noises: With the engine off, press the window switch. If you hear a hum or click from inside the door, power is likely getting to the motor. If you hear nothing, the problem is more likely the switch or wiring.
3. Perform the "Dim Lights" Test: At night, turn your headlights on and try the window switch. If the headlights or interior dome lights dim slightly when you press the switch, it confirms the motor is receiving power but is seized and drawing a heavy electrical load.
4. Test for Voltage: This is the most definitive test. You'll need to remove the door panel to access the motor's 2-pin electrical connector. Unplug it and use a multimeter to test for voltage at the connector's pins while a helper presses the window switch. You should see approximately +12V in one direction and -12V in the other. If you have voltage here but the motor doesn't work, the motor has failed.

Buying a Used Power Window Motor: What to Look For

A used OEM motor is often a reliable and cost-effective alternative to a new aftermarket part. Here’s what to check before you buy.

• Why Used OEM? The original Subaru motors are built to a high standard. A used OEM part from a low-mileage vehicle can often outlast a brand-new, cheaply made aftermarket motor. Fitment is also guaranteed.
• Verify the Connector: The front window motors on this Forester generation use a 2-pin connector. You must verify that the replacement motor has this same connector. Remove your door panel and look at your original motor's plug before ordering.
• Inspect the Gear: Look at the small gear on the motor that engages with the regulator. It should be free of chips, cracks, or excessive wear.
• Consider the Regulator Assembly: It is often easier to buy the motor and regulator as a single used assembly. This makes installation simpler as you won't have to separate the old motor from the old regulator inside the door.
• Pro Tip from the Forums: On the Forester, the front left (driver) motor is the same part as the rear right (passenger) motor. Likewise, the front right motor is the same as the rear left. When sourcing a part from a salvage yard, pull a motor from a rear door. Rear windows are used far less often, so the motor will have significantly less wear and tear.

Replacement Overview & Difficulty

• Difficulty: 2 out of 5. This is a very manageable DIY job for a beginner with basic hand tools.
• Time: 1 to 1.5 hours.
• Tools: Phillips screwdriver, 10mm socket and ratchet, and a trim removal tool. An impact screwdriver can be helpful for the motor screws, which can be very tight.

The basic process involves removing the interior door panel, carefully peeling back the plastic weather barrier, and supporting the window glass in the 'up' position with tape or a wedge. The motor is held to the regulator by three Phillips head screws. You will likely need to loosen the 10mm bolts holding the regulator to the door to create enough space to wiggle the motor out.

Cost Comparison

Prices can vary, but here is a general breakdown of what to expect:

Frequently Asked Questions (FAQ)