Don’t worry about EV battery

Q: What happens to an electric motor power source battery in an EV, plug-in hybrid or hybrid if it is not used for 6 months or more when we go south for the winter? I am familiar with putting a gasoline engine battery on a maintainer.

A: Propulsion batteries last a surprisingly long time because they use lithium-ion cells. Hybrids and EVs can sit for months without requiring charging. At the ideal 80% charge, they may lose only 2-3% per month. One caveat: Extreme heat (over 110 degrees) and extreme cold (near zero) for long periods shorten the time. Don’t worry if you’re a snowbird.

Q: In your column about road noise and electric vehicles, you got a metric conversion wrong. One-tenth of a liter is not one third ounce. It’s about 3 ounces. A liter is a little larger than a quart. I’m not saying your answer is wrong — maybe the crankcase can safely hold an extra three ounces and change. But it’s not a matter of a third of an ounce.

A: You’re right. It’s three ounces. I believe I misplaced a decimal point. (I should avoid doing math in public.) And yes, those three ounces won’t make much of a difference.

Q: I’m a former auto technician, and I have something to add to your reply to a person speaking of front wheel shimmy at 50 mph. I’ve chased this type of problem often over the years. It’s not always a wheel balance issue. I found the brake rotors also can cause a shimmy. I recently replaced the rotors on my own car and it’s now smooth as glass at all speeds.

A: Right. A warped or bent brake rotor is often the cause of a shimmy. It doesn’t take much to cause this issue. In fact, an unskilled worker installing a wheel and tire may torque the lug nuts unevenly, thus creating the problem. Best practice is to use a torque wrench or at least torque sticks to evenly tighten the nuts.

Q: Apparently if the seal around the tire does not seal correctly, the tire loses air. A friend told me that was the problem on my 2020 Malibu. I’ve had the tire checked. No issues. So, I have to just keep putting air in the tire.

A: Slow leaks are hard to find — particularly if the leak is where the tire meets the rim. Corrosion, especially on alloy rims, is the issue. Corrosion eventually leads to pitting, allowing air to seep out. A good tire shop can remove the tire, sand off any corrosion, clean the tire’s bead and remount the tire on the rim using bead sealer. Unless the rim is terribly pitted, this works.

Bob Weber is a writer, mechanic and ASE-certified Master Automobile Technician. His writing has appeared in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to motormouth.tribune@gmail.com.