How does maintenance on electric vehicles differ from internal combustion engine vehicles? Because EVs have fewer moving parts and don’t require oil and other fluid changes, are they are cheaper to maintain?
Over the next few weeks, we are going to break down EV maintenance, hopefully helping you decide if an EV is right for you. I enlisted the help of a friend who is a senior service adviser at a Tesla centre. It’s not my intent to be narrow-sighted and focus only on EVs produced by Tesla as I understand there are many manufacturers producing EVs, however Tesla has the most vehicles on the road and they have been there for the longest time, resulting in more useful data.
Regenerative braking is a good place to start as this is one of the key major differences with EVs. In EVs, plug-in and hybrid vehicles, when you remove your foot from the throttle, the electric motor turns into a generator, harnessing kinetic energy, thus charging its batteries and slowing down the vehicle.
Drivers of EVs adapt to a new driving style and get used to the vehicle slowing down on its own without the need to always apply the brakes. This is becoming recognized and known as one-pedal driving. One would think this allows the brakes of an EV to outlast their ICE counterparts, however fewer brake applications result in two problems – brake components that seize and brake rotors that corrode prematurely. Firstly, the pins that the brake calipers slide on suffer from lack of use, eventually becoming frozen. This will lead to a brake caliper that exerts more force on the inner brake pad, with the outer brake pad performing far less actual braking. This imbalance in braking force can result in an inner pad wearing out earlier than the outer.
Secondly, all drivers, regardless of what kind of car they drive, recognize this noise when they depart for their first drive in the morning after a rainy night. That crusty noise that occurs when you first apply your brakes and generally goes away after 30 seconds. This noise is because a thin layer of corrosion has settled on the brake rotors overnight. Your first few brake applications in the morning effectively wipe away this corrosion. However, using the brakes less allows this corrosion to build. Plus, the brakes on an EV don’t get as hot, heat that is needed to burn off moisture. Left unchecked, this corrosion builds up to the point where brake rotor replacement is the only repair path.
Tesla recommends a thorough brake service once per year to combat the corrosion and lubricate all the slider pins regardless of mileage driven. EV owners who haven’t visited their dealers for several years are often surprised with unexpected brake repairs even though they may not have put that many kilometres on their vehicle.
The service adviser also brought up a good point regarding single-motor versus dual-motor EVs. With the dual-motor vehicle, the regenerative braking is applied to all four wheels, but with a single motor the regenerative braking is only applied to two wheels. Results of this are felt in the two driving tires of the single-motor EV. The regenerative braking forces are only being absorbed by these two wheels. Unfortunately, the two tires doing all the work may wear prematurely if the driver doesn’t learn to moderate their throttle to gradually slow the vehicle. More on this subject next week.
My wife’s 2018 Subaru Forester has a CVT transmission. Since new we’ve noticed a lag when shifting to drive from reverse that was initially annoying, but we have since become used to.
The dealer says this lag is typical of CVT transmissions. Coincidentally we received a notice from Subaru advising that they had extended the warranty on the transmission to 10 years. They claim there is no issue that prompted this warranty extension, but rather it is because of their faith in the reliability of the transmission.
First, is the lag in a CVT transmission normal and second, would you, too, be suspicious of the warranty extension?
Thanks, Paul M.
The lag you refer to should be no longer than a second or two, anything more would be cause for concern. Internet forum participants commonly complain of this lag in their own Subaru vehicles, so you are not alone.
My own opinion on warranty extensions, regardless of manufacturer, is they are usually put into place to combat or pre-empt lawsuits and general negative reviews from unhappy customers. While their reasoning may be in dispute, I applaud Subaru for making the tough decision to put their customers first.
I am just finishing reading your article on garages “throwing each other under the bus.” I am a licensed mechanic and have been in and out of the trade since the mid 1970s. You nailed it with your article – I have always felt that way and we look so unprofessional. It takes away from the little trust that many have. It’s a pet peeve of mine and when I taught auto at the secondary level, I made a point of working with my students to not behave this way when they got into the trade.
Thanks for the great read.
Like anything else in life, it’s the loudest few who do the most damage. Combine the negative way of looking at things some people suffer from, along with auto repair shop personnel who can only elevate themselves by diminishing others, and these unattractive, unprofessional stereotypes are cemented in. I have no clue how to fix it, all I can do is to try to move our trade into a positive direction by being at my best with my customers and my competitors alike. Maybe my attitude will affect another business owner in a positive way and help spread kindness, trust and professionalism in our trade.
Lou Trottier is owner-operator of All About Imports in Mississauga. Have a question about maintenance and repair? E-mail email@example.com, placing “Lou’s Garage” in the subject line.