Maintenance and Electric Cars

by Chris Chase

With its relatively new technology, electric vehicle (EV) ownership raises a lot of questions. We’ve already answered a couple of them in our articles about how long it takes to charge an EV and how much charging one costs.

Some other common ownership questions revolve around electric car maintenance. Do EVs need oil changes? Do they have any other fluids that need to be changed regularly? Since electric cars tend to be more expensive to buy than comparable gas-powered models, does that mean it also costs more to take care of one?

And what about Tesla maintenance? That company specializes in high-profile, high-performance EVs that are among the most desirable battery-powered vehicles available. How does a Tesla’s maintenance needs differ from those of other EV makers?

To answer these questions, we looked at the maintenance schedules in the owner’s manuals for a handful of EVs on the market right now. Two of those are the Chevrolet Bolt and Hyundai Kona EV, both of which cost roughly $45,000 and boast about 415 km of driving range. Our third subject is the Tesla Model S, the brand’s mid-size sedan model, which promises 373 km of driving range for its $109,000 Canadian starting price.

First, a note about vehicle maintenance schedules. For most cars, the owner’s manual will list at least two schedules: one for normal driving and another for severe use with shorter, more frequent maintenance intervals. Driving during the winter in most parts of Canada counts as severe use in the eyes of most carmakers, so any specific maintenance intervals we’ve included here are from the manufacturer’s severe-use schedule.

Also, every car’s needs are different, so always follow the maintenance schedule in the owner’s manual for your specific model.

Do EVs need oil changes?Mitsubishi Outlander PHEV

No. An electric motor has far fewer moving parts than a gas or diesel engine and does not need oil to keep it lubricated, so there’s no oil to change.

What about transmission fluid?

A typical EV has a single-speed transmission that is simpler than the multi-gear or continuously variable transmissions in gas and hybrid cars. An EV’s transmission does contain lubricating oil, but of the EVs whose maintenance needs we looked at for this article, only the Hyundai Kona EV needs its transmission fluid changed every 120,000 km, which means once every five or seven years if you drive about 20,000 km per year.

What regular maintenance items do EV owners have to worry about?

Battery cooling/heating system

While an EV doesn’t need a cooling system for an engine, it does have one for the battery. It uses the car’s air conditioner to keep the battery cool in hot weather, and an auxiliary electric heater warms it in cold conditions. It’s similar to a gas-powered car in that it uses liquid coolant, so its level needs to be monitored in case of leaks and may have to be replaced at specified intervals (though Tesla says its battery coolant should last the life of the vehicle). It’s also important to make sure the car’s air conditioning system is working well.

Brakes

EVs have regular hydraulic brakes that use friction between brake pads and rotors to provide stopping power. They use the same kinds of brake fluid as regular cars, so all you have to worry about is using the grade recommended by the manufacturer.

Brake fluid can leak from faulty or worn brake lines, and the fluid itself has a lifespan. Chevrolet says the brake fluid in its Bolt EV should be changed every five years. Tesla recommends checking it every two years and replacing it when necessary. Hyundai says the Kona EV’s brake fluid should be inspected every 24,000 km, or once a year.

An EV’s advantage is that its regenerative braking system does a lot of the work, especially if you drive gently, and that means less wear and tear on the friction brakes. The disadvantage is that if the friction brakes are used less, they can be more susceptible to problems caused by corrosion, like seized calipers and rusty rotors. Brake calipers should be inspected and lubricated (if necessary) about once a year in any car.

Tires

There’s nothing magic about an EV’s tires. They’re still made of rubber and wear out as you drive, so they should be rotated regularly to avoid uneven wear. And while most EVs have a tire pressure monitoring system, you will still have to add air if it tells you a tire is low.

Suspension

Suspension components will wear out and require replacement at about the same rate as a comparable gas-powered car. In cars with traditional shock absorbers, watch for signs of fluid leaking from the shocks. Worn suspension and steering parts will make knocking, creaking or other sounds while the car is driving.

Inspect the rubber boots around the ends of the drive axles for holes and tears. A worn drive axle may make clicking or grinding sounds, especially while making turns.

Other EV maintenance items

Like all modern cars, EVs have a cabin air filter to keep things like dust and pollen out of the car’s interior. Replacing the filter is usually an easy job you can do yourself.

There’s also nothing special about an EV’s windshield washer system. The car will probably flash a warning light or alert message when the fluid level is low, and the reservoir is under the hood, right where it would be in a gas-powered car.

Do you need to find a specialized electric car mechanic?

In theory, any repair shop can look after routine services like replacing tires, brakes and suspension parts. Some independent garages might be hesitant to do any work on EVs if they’re unfamiliar with them, so it might be hard to find a non-dealer shop to work on your EV.

Electric vehicles have high-voltage electrical systems that do require special knowledge to work on, so any repairs related to the battery and drive system are best left to a technician with specialized training.

If you buy a new EV, your best bet is to get it serviced at the dealer or, in the case of Tesla, by the company’s mobile technicians.