Are you noticing a grinding noise when you accelerate your car?
Keep reading to learn about the five most likely causes of this, how much they’ll cost to fix, and whether or not it is safe to continue driving your car in the meantime.
Is it safe to drive if you hear a grinding noise?
Because there is a range of potential problems that may be leading to the grinding noise you’re hearing, it’s best to prioritize getting your car checked as soon as possible.
The grinding sound may indicate a car issue that makes it dangerous for you to be on the road.
Top Causes of a Grinding Noise When Accelerating
Learn five of the most likely reasons why you’re hearing a grinding noise upon acceleration and how much they cost to fix.
1. The Transmission
A car’s transmission is an essential part of it functioning properly, as it controls the amount of power transferred from the engine to each wheel.
Problem
If you’re hearing a grinding noise when you accelerate, one potential cause is your car’s planetary gear system.
When functioning correctly, this system matches the speed of the car’s wheels to the speed of the engine.
If you’re hearing grinding while accelerating, putting your car in gear, or reversing, this may indicate your wheels and engine are out of sync.
IMPORTANT: This can cause serious damage to your transmission. Get your car repaired as soon as possible if this is suspected.
Fix
If the grinding noise comes from the transmission, it will need to be repaired or replaced.
If you’re lucky enough to get the problem diagnosed in time, you may be able to get it repaired.
This generally costs $2,500-$4,000.
However, it is more likely that it will need to be fully replaced once you are hearing the grinding noise because even the slightest amount of damage will throw your transmission out of sync.
A new transmission costs $4,000-$8,000.
IMPORTANT: It is highly recommended that you DO NOT repair or replace your transmission yourself. Because of its complexity, a professional should handle it.
2. The Differential
The differential is the piece of your car’s drivetrain that when functioning properly, allows your wheels to rotate at different speeds.
It transfers power from the engine to each wheel, splitting it between them all.
Problem
If it’s not functioning properly, driving your car will be unpredictable and extremely dangerous.
If the grinding noises are coming from the differential, you will likely notice them while you are speeding up or turning.
Fix
If the sound you’re hearing is more of a whirring or whining than a grinding, this may indicate the system is just low on fluid.
The fluid in the differential system lubricates the gears, preventing them from scraping together. Fixing a fluid leak generally costs as little as $70 to $150 to fix.
If the sound has progressed to resemble grinding, prepare to replace the differential. This typically costs $1,500-$4,000.
3. A Wheel Bearing
A car’s wheel bearing connects the wheel to its axle, allowing each of your car’s wheels to spin with minimal friction.
Problem
A grinding noise while driving may indicate that your wheel bearing is either damaged or entirely worn out.
The noise will most likely be noticed when you are turning.
If this is the problem, you might notice poor steering and handling or uneven wear on your tires.
On top of this, it can cause issues for your transmission, CV joints, and wheel hubs.
IMPORTANT: This problem cause your wheel bearings to lock up while driving, which is seriously dangerous for you, anyone else in your car, and anyone else on the road. If this problem is suspected, do not drive your car.
Fix
If your wheel bearing is worn out, you must replace it.
If you are knowledgeable enough to DIY this fix, you can do the job for an estimated $60 to $150.
Taking your car to a professional for a wheel bearing replacement is estimated to cost around $300.
4. The CV Joint
The CV joints (aka constant velocity joints) connect the car’s transmission to its wheels. They are often used on front-wheel-drive cars.
Problem
Indications the CV joints may be failing include: noticing a grinding, knocking, or clicking sound when you accelerate, grease in the inner edges of your tires, or a vibrating sensation when you drive.
If you ignore this issue, your car may get stuck in park.
IMPORTANT: CV joint issues compromise the control you have over your vehicle. These need to get fixed right away.
Fix
A worn-out CV joint needs to be replaced.
If you want to save money and do it yourself, this fix generally costs $95-$210.
Having a mechanic replace your CV joint will likely cost between $650-$1,300, including parts and labor.
5. The Motor Mount
A car’s motor mount—otherwise known as engine mount—is responsible for holding the engine in place. Your engine is a particularly heavy car part.
Problem
Because it’s made of metal, it can corrode, break, or separate from the engine.
If this is the cause of your car’s grinding noise, you will likely hear it while you are speeding up.
This suggests the engine mount has either shifted or fully become unmoored, meaning it is moving around inside the engine bay.
IMPORTANT: Get this fixed swiftly, as it can cause serious damage to your car’s serpentine belt, swirl pot hose, and other components. The more damage, the more expensive the fix.
Fix
You can fix a worn-out or loose mount if you have the appropriate knowledge, tools, and experience with welding. In this case, you can expect parts to cost approximately $100 to $300.
If you take your car to a mechanic, it will cost about $800 for them to re-secure your car’s motor mount.