Ask a Mechanic: The safety and convenience of a professional oil change

Every week, we take your questions about what is going on under the hood of your vehicle and pose them to a knowledgeable mechanic in the Greater Toronto Area. In today’s column, we learn about machining rotors and safely completing an oil change.

Dear Ask a Mechanic,

I drive a Toyota Corolla. On occasion the dealership tells me I need to have the rotors machined as there is rust on them. I am very reluctant to machine the rotors. I don’t drive a lot and am easy on the braking. I worry about the machining as it removes the rotors surface, then the next thing is I have to get new rotors. Does regularly braking clean up the rotors and should I have them machined when the dealership recommends it? — Clean Brake

Andrew Le, co-owner of 1 Four 0 Nine Inc. in Toronto, sees this two ways. If rotors are rusty from customers not driving their vehicle, he does recommend getting them machined. The process involves restoring the metal on the rotors to a smooth, flat service, to allow for some of the friction required for brakes to properly work to be restored. However, this may not be possible if the rotors have substantial corrosion.

Before taking your vehicle to a dealership it might be best to drive it around a little. Le said if your car is sitting for a couple of days and the rotors gather minor surface rust, driving and using your brakes will help get rid of this rust.

But in his opinion, if the rotors need work, he recommended getting them replaced because it’s inexpensive and easy to do so, especially for popular vehicles, like a Toyota Corolla. “I don’t believe in machining anymore because rotors are just so cheap,” he said. His opinion changes if the vehicle is rare or very expensive, as parts would be harder to find and costlier.

Keep in mind, the corrosion on the rotors can cause uneven wear on the brake pads, so they should also be inspected and replaced if needed.

Dear Ask a Mechanic,

I always see people doing their own oil changes and I’ve noticed oil is readily available in many stores that sell car goods. I want to change my own oil as means of saving money. Why should I see a mechanic for this instead of doing it myself? Is there some sort of benefit?

— Oil Changer

The availability of products to complete the task does make it easy to be done at home but the biggest benefit, Le said, is safety. Vehicles have plugs that require tools to remove. Located underneath the vehicle, the process requires a car to be hoisted into the air. Those doing this task at home would likely use a jack and jack stands to achieve this.

“You can do it but it’s very risky, especially if you’re jacking up the car, and there’s no support,” Le said. “One sudden move and it could fall down and possibly kill you.” Bringing it to a mechanic allows them to use a hoist, making the process safer, he said. “It’s worth it to spend that money and have it done safely and professionally.”

There is also a major convenience factor to having your oil changed professionally. In addition to having to select the correct type and quantity of oil, and choose the right filter, you also need to dispose of the used oil and filter. They must either be taken to an appropriate hazardous waste facility or disposal centre that accepts them. A mechanic will do that as part of the services they offer.