What does a failing Subaru transmission sound like?

A failing Subaru transmission often shows up as a whine or whir before, during, or after shifting, plus occasional clunks, grinding, or buzzing. The exact noise and when it happens can help point to the likely culprit.

Subaru uses different transmission types across its lineup. In most recent models, the Lineartronic continuously variable transmission (CVT) drives the wheels, while some older cars use traditional automatics and a few sports cars use manuals. No matter the type, sounds ranging from a high-pitched whine to a metallic rattle can signal wear, fluid issues, or internal damage. If you notice persistent noises along with other symptoms such as slipping, rough shifts, or engagement delays, have the vehicle inspected promptly to avoid further damage.

Common noises and what they may indicate

Here are the noises Subaru owners frequently report and the general issues they can signal. Listen for when the noise occurs (idle, under load, at specific speeds) to help inform a diagnosis.

• Whining or whirring noise that rises with engine speed or vehicle speed, often coming from the transmission area. This can indicate low transmission fluid (or a leak), worn bearings, a failing pump, torque converter issues, or belt/chain concerns in a CVT.


• Clunking or banging on shifts or engagement. This can point to worn gears, a hydraulic issue, or torque converter lockup problems in traditional automatics or misbehaving CVT pulleys in a CVT.


• Grinding noises during shifting. Typically signals internal gear wear, damaged synchronizers in a conventional automatic, or severe CVT belt/chain wear with misalignment.


• High-pitched buzzing or metallic rattling at specific speeds. Often related to CVT belt tensioners, worn CVT pulleys, or bearing wear inside the transmissions.


• Hissing or wind-noise-like sound under acceleration. Could indicate a problem with the CVT hydraulic system, a leak in the valve body, or belt contact irregularities in CVT.


• Low-frequency rumble or hum that changes with road speed. Might be transmission-related gear train or torque converter issues, or could reflect associated driveline components; a professional check is advised.


• Slipping or loss of acceleration with accompanying noise. This is a serious sign that transmission pressure or belt/gear integrity is compromised and requires immediate service.

Notes: Not all noises mean the transmission is failing, and some sounds can be caused by related systems such as the engine, exhaust, or differential. A proper diagnosis should involve a capable technician and may require a road test and a transmission-fluid check or code scan.

CVT-specific vs traditional auto sounds

Depending on whether your Subaru uses a CVT or a conventional automatic, the sounds you hear can point to different issues. CVTs (Lineartronic) tend to produce smooth whines and belt-related noises, while traditional automatics more often exhibit clunks, gears grinding, or torque converter issues.

• CVT (Lineartronic): common sounds include a gentle, continuous whine or whir at varying speeds, occasional belt noise under heavy load, and a faint rattle if pulleys or the belt is worn. Severe CVT faults can produce buzzing or a louder, metallic rattle.


• Traditional automatic: more likely to present with distinct clunks on shifting, grinding gears during engagement, or a metallic rattle from torque converter issues.

Because Subaru has used CVTs in most models for years, the familiar "whine under load" is often the signature. But any unusual sound should prompt inspection to avoid further damage.

What to do if you hear a concerning transmission sound

Proactive steps can help prevent more costly repairs and help a technician diagnose the issue more accurately. The following actions are practical and safe to perform before a mechanic evaluation.

Before attempting any DIY fixes, keep in mind that transmission problems can be internal and dangerous to diagnose without proper tools. The instructions below are for taking initial observations and safe steps only.

• Check the transmission fluid level and color (if accessible). Low fluid or dark, burnt-smelling fluid can indicate problems or impending failure. Do not overfill.


• Check for leaks under the vehicle and around the transmission pan. Leaks can lead to low fluid and overheating, accelerating wear.


• Note when the noise occurs: at start-up, idle, during drive, under acceleration, or when turning. Also note whether the sound changes with speed or gear, and if there is accompanying slipping or delays in engagement.


• Scan the vehicle’s onboard computer for trouble codes. A code can point to solenoids, sensors, or other transmission controls and help guide the inspection.


• Drive with caution—avoid hard acceleration, heavy towing, or high-speed driving until a diagnosis is complete to prevent further damage.


• Schedule a professional inspection promptly if noises persist or are accompanied by slipping, failure to engage, limp mode, or fluid leaks.

Timely diagnosis is key. Subarus with CVTs may require specialized knowledge and tools to examine belt wear, pulley operation, valve bodies, and fluid condition. A trained technician can confirm whether the noise stems from the transmission or another component in the driveline.

Summary

When a Subaru transmission begins to fail, the sounds typically fall into a few categories: a whine or hum from the CVT or torque converter, clunks or bangs on shifts, grinding during engagement, or a buzzing/rattling at certain speeds. Each noise has potential causes—ranging from fluid issues to worn bearings, belt/chain wear, or internal gear damage. If you hear persistent, unusual transmission noises, have the vehicle inspected promptly by a qualified technician who can test drive, inspect fluid, and check for fault codes to prevent further damage.

How to tell if a Subaru transmission is bad?

Common symptoms of Subaru transmission problems include difficulty shifting gears, unusual noises like grinding or humming, and transmission fluid leaks. Other signs to watch for are a burning smell, slipping gears, a delayed response when accelerating, shuddering or shaking, and dashboard warning lights like the check engine light.
 
Common symptoms

• Difficulty shifting: You may experience hesitation, jerky movements, or a failure to shift into gear. 
• Unusual noises: Listen for grinding, humming, whirring, clunking, or popping sounds, especially when shifting or in neutral. 
• Fluid leaks: Look for reddish-brown, sweet-smelling fluid under your car, which is a sign of transmission fluid loss. 
• Burning smell: An acrid or burning odor can indicate that the transmission fluid is overheating and degrading. 
• Slipping gears: The transmission may shift into a gear and then immediately pop out, or the engine may rev up without a corresponding increase in speed. 
• Delayed response: You might notice a pause or hesitation after you shift into gear before the vehicle starts to move. 
• Vibrations and shaking: The vehicle may shudder, shake, or jerk, particularly during shifts. 
• Dashboard warning lights: A "check engine" light or other transmission-specific warning lights can illuminate to signal a problem. 
• Stalling: Some Subaru CVTs have been known to stall out while driving. 

What to do
If you notice any of these symptoms, it is important to have your transmission inspected by a qualified mechanic as soon as possible. Addressing issues early can help prevent more serious and costly damage.

What does a failing transmission sound like?

The noises most commonly heard as a transmission is beginning to experience problems are whining, buzzing, grinding and clunking. It's hard to know exactly what is causing the strange sound. Perhaps it's a small part, or maybe a major component that makes up your transmission.

What does a bad Subaru CVT transmission sound like?

If you have noticed delayed acceleration, shuddering, or a high-pitched whining sound, your Subaru's CVT may need attention.

What happens right before your transmission goes out?

You can tell your transmission is about to go out by listening for strange noises like grinding or humming, and by experiencing symptoms like rough or delayed shifting, slipping out of gear, and a burning smell. Leaking reddish-brown fluid on the ground under your car is another strong indicator of a transmission problem. If you notice these signs, it's crucial to have a professional inspect the vehicle to prevent further damage. 
Signs of a failing transmission

• Strange noises: Listen for grinding, clunking, humming, whining, or buzzing sounds, especially when shifting or in neutral. 
• Rough or delayed shifting: You may feel a jolt, a delay, or a jerky sensation when the car changes gears. 
• Gear slipping: The transmission may randomly shift out of gear, or the engine may rev up without the car accelerating as it should. 
• Burning smell: A distinct burning smell can indicate that the transmission fluid is overheating and burning. 
• Leaking fluid: Look for red or brown fluid puddles under your car, which could mean a transmission fluid leak. 
• Warning lights: The "Check Engine" or other warning lights on your dashboard may illuminate, says Hogan & Sons. 
• Poor acceleration: The vehicle may feel sluggish or not accelerate as powerfully as it normally does. 

What to do
If you experience any of these symptoms, have a transmission specialist diagnose the issue immediately. Continuing to drive the car could lead to more severe and costly damage.