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How to break in your new electric car

It may not have an engine, but your EV still needs a break-in period.

Many of you are getting your first EV (electric vehicle), and whether it's a Nissan Leaf, a Tesla Model 3 or a Chevrolet Bolt, somewhere in the back of your mind is probably the question, "How do I break it in?"

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In one sense, you don't. There is no powertrain break-in period for an electric car that is analogous to that of a conventional car, since an EV's battery and motor aren't friction-based. But the rest of the car will benefit from some break-in work you may not know about. 

No break-in?

The main reason conventional cars have a break-in period is to hone the inside of the cylinder walls and the outside of the piston rings, which is more than many drivers even comprehend. Suffice it say that letting those parts marry via friction with moderate driving the first 500 to 1,000 miles allows the engine to deliver better performance for more miles in the future. 

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Here's why you break in a conventional engine: To let the piston rings and cylinder walls hone each other to a finely mated finish. Ditto for the crank journals and bearings, lower in the engine. But your EV, blessedly, has none of these parts.

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But your new EV doesn't even have those parts, let alone an engine, and no EV owner's manual or technical forum we've scoured makes any case for breaking in an electric car's motor. So, instead, your attention should turn to tires and brakes.

Breaking in brakes

While a lot of EV braking is done by the resistance of regeneration, your electric car still has traditional disc and pad friction brakes. When they are eased into service over the first 500 miles their surfaces have a chance to mate better, providing you with more miles of quiet, smooth operation than if they're subjected to harsh service from the outset. 

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What's old and dumb and still found in your new electric car? Friction brakes, which work a little better and last a little longer if you break them in gradually.

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And I bet that anything that lengthens the time between now and an expensive brake service on your car is going to get your attention.

Preventing tired tires

Another place EVs have a lot in common with conventional cars is tires, and new tires need breaking in. Your first 500 miles of driving apply load, lateral force and heat cycling to the complex sandwich of rubber, cords and belts that makes up a modern tire. 

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The complex sandwich that makes up the modern tire can benefit from a few hundred easier miles at first.

U.S. Tire Manufacturer's Association

That process sets the whole assembly so it will perform better, longer. This might be even more important on an EV, which tends to be heavier than a conventional car of the same class and can provide prodigious torque that tortures tires. Also, new tires are very smooth and have a sort of lubricant on them left over from the molding process. Scrubbing them up with gradual driving over the first 500 miles means you won't be caught with less traction than you expect.

What about the battery?

Most of us are conditioned to be nervous about how and how often we charge our battery-powered gear, fearful that we'll shorten a battery's life or introduce "memory" that prevents it from accepting a full charge. My take on this is that any electric car that needs you to babysit its battery needs to be traded in for something grown-up. EVs have sophisticated battery management and cooling systems to take battery conditioning off your plate. The manufacturer has already sold you range anxiety and the longest "refueling" times of your life, the least it can do is manage the battery. No modern EV owner's manual or Tesla delivery experience we reviewed makes any mention of having to baby the battery in a break-in period.