Below are the most popular Car Doctor questions asked in 2025.
Q. My question is that I recently switched my oil changes from regular oil to synthetic. My car is a 2009 Camry LE with about 145,000 miles on it. The shop where I had the work done said that once I switch to synthetic oil, I can’t go back to using regular oil. Is the shop correct? Why would they say this?
A. There is no reason you can’t switch back to conventional oil although you may not want to. In most cases synthetic oil starts life as conventional oil and then is highly processed with different additive packages. Many shops are only using synthetic or blends these days. Synthetic oil offers better lubrication at all temperatures and easier engine starting in cold weather.
Q. My car battery is 7-years-old and the car starts just fine. Should I change it or can it go longer?
A. The average life of a battery in the Northeast is just under five years. Recently AAA replaced a 15-year-old battery. I have personally had a battery last seven years and also replaced one at four years old My advice is unless you test your battery on a regular basis, replace it before it leaves you stranded.
Q. When I talk with people about maintaining their cars I hear all kinds of advice. Even when I go to the dealership the personnel don’t always agree on when regular service should be performed. As an example, I have been told with my Toyota Corolla the oil should be changed every 3000 miles. I have also been told the oil should be changed yearly. How do I know what is right?
A. Whenever in doubt, I refer to the vehicles owner’s manual. In the case of your Toyota the owner’s manual could list an annual oil change yearly or every 10,000 miles whichever comes first. What is important with long service intervals is that you routinely/monthly check vital fluids, tires and tire pressure as well as drive belts and coolant hoses. Spending a few minutes every month checking these items can help prevent a breakdown on the road.
Q. As I get older, I’m finding it a bit more challenging to drive at night. I’m going to use one of the headlight restoration kits to clean the headlight lenses on my Camry (I did them approximately 3 or 4 years ago and it seemed to help a bit). I’m also thinking of changing the headlight bulbs. I typically would just but whatever they have at the local auto parts store for comparable bulbs. However, I did some research on the internet and came across LED headlights; they get very good reviews and are supposedly “brighter” than the regular halogen bulbs that came with the vehicle. My question is – is it ok to use LED type bulbs in place of the regular halogen type bulbs? I plan to replace all four bulbs.
A. Unfortunately as we age, we need more light to see. In fact we need three times as much light to see at age 60 than at age 20. Aftermarket LED bulbs that replace conventional headlights are actually illegal and violate the Federal Motor Vehicle Safety Regulations. The issue is they are brighter but not particularly well focused. This extra light, dazzle and poor beam pattern also can blind oncoming drivers. Personally I have had good results with Sylvania Silver Star Plus bulbs. The Sylvania bulbs seem brighter and whiter. Although like most high-performance products, they don’t last as long as the stock blub. The other issue with LEDs replacement bulbs is that sometimes they can cause electronic issues. These issues can be minor such as a warning light illuminated or in some cases, I have seen the body control computer fail due to a poorly made LED bulb.
Q. I recently purchased a new Genesis GV70 which to date has been the nicest vehicle I have ever owned. The dealer told me that I need to have it served at a Genesis dealer to maintain the warranty. This was not the case with my last car, is this true?
A. That is false. You can have an independent shop do repairs and perform regular maintenance. You can even perform the service yourself. What is important is that you use original or a quality aftermarket part that meets the original specification. Also document all service performed with the date and mileage. This way if there is a warranty question you will have the documentation that the work was performed as required.
Q. When I step on the brake, I get a vibration. The steering wheel shakes a bit. I took the car into my local shop, and they said the brakes were okay but the brake rotors were out of round. I had the brakes replaced and now all if fine. How do I avoid this from happening again.
A. The number one reason that brake rotors become distorted is due to poorly tightened wheels. Whenever a tire/wheel is installed on a vehicle it should be tightened with a torque wrench to the specified “tightness”. Fully tightening a wheel with an impact wrench or even improperly by hand can cause a brake vibration. The vibration may not happen immediately but will show up over time.
Based in Rhode Island, Jillian Young is AAA Northeast’s director of public relations. She regularly appears in local TV, radio and print media to discuss traffic safety, travel, insurance and more.
