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CanadaBrake Pads on Electric Vehicles
With the number of electric vehicles (EVs) on the road steadily increasing, it won’t be long before EVs start coming into your shop for maintenance. There are many differences between EVs and traditional gas-powered vehicles, including the braking system. Electric vehicles are equipped with two braking systems that work together:
- Regenerative braking system
- Traditional friction-based brake system
While the regenerative braking system handles a large portion of the braking duties, the conventional brakes kick in once the limits of the regenerative brakes is reached or during emergency and panic stops. Since the conventional brake pads aren’t used as much, they typically last longer than the pads on a conventional vehicle with an internal combustion engine (ICE). While it’s easy to think that the brake pads and rotors will last the lifetime of the vehicle, this nonuse can affect the ability of the brakes to do their job. These important parts still need maintenance.
Rust and EV Brakes
Because an EV’s brake components such as the pads, rotors and caliper slide pins are exposed to rain, salt and debris, rust is the issue that can cause premature failure of brake pads. On a gas-powered vehicle, rust is quickly burned off as the brakes are used, but on an electric vehicle, brake pad rust doesn’t have a chance to get scraped off because the pads aren’t used as much. The rust can build up and result in diminished performance when the conventional brakes are used.
On a conventional ICE vehicle, the brake pads need to be replaced because the friction surface wears down while on an EV, the brake pads may need to be changed because of rust building up due to infrequent use. Servicing the brakes on a regular basis is the best way to ensure that the brakes are ready in any situation.
What Needs to Be Cleaned?
Moving parts in the brake system need to be cleaned and lubricated as needed. Follow the manufacturer’s recommended service schedule for brakes.
Brake Pads
Remove brake pads from the caliper and inspect. Use a wire brush to remove surface rust. Focus on the back of the pads and the brake caliper mount.
Rotors
Remove surface rust with a wire brush.
Calipers
Check for rust and grease caliper slide bolts with the appropriate lubricant to avoid seizing. Over time, the grease breaks down or is washed away by rain. Clean brake caliper mount removing any rust with a wire brush and apply grease to the slotted area that holds the brake pad tabs.
What About Brake Fluid?
Follow the manufacturer’s recommendation for replacing the brake fluid; pay attention to both the mileage and months. Brake fluid degrades when not being used; it absorbs water from the atmosphere and breaks down.
Brake Burnishing Procedure
Burnishing the brakes is not only important to do when installing new brakes, it can also help remove surface rust on brake components.
- Driving on a straight road, get the vehicle up to 50mph.
- Press down on the brake pedal with consistent pressure to slow the vehicle. Release the brake pedal when the vehicle gets down to 10mph.
- Complete the procedure six times; waiting 30 seconds between cycles.
Diagnosing Brake Noise
Just as with traditional ICE vehicles, the brakes on an electric vehicle can make grinding, squealing, squeaking and other noises. In fact, because an EV tends to be quieter than a conventional vehicle, brake noise can be more noticeable. Typically, a grinding noise is related to surface rust on brake components. Following the burnishing procedure can remove surface rust. If the noise persists, cleaning the brake components may solve the issue.
Learn more about quality brakes, find your car part, or find where to buy your auto part today.
The content in this article is for informational purposes only. You should consult with a certified technician or mechanic if you have questions relating to any of the topics covered herein. Tenneco will not be liable for any loss or damage caused by your reliance on any content.