See more of the story

Q: While we were coming back from vacation, the splash shield on our 2013 Mazda3 came loose. We pulled over and had it taken off by a local auto shop. I asked them at the time if it was OK to drive without it on, and they indicated that as long as I was on a road it was OK. When we got home, I took it over to my local mechanic that I have used for many years for all my auto repair needs. He took a look and said that I really didn't need to replace it because a majority of the cars on the road now don't have one. Should I get it replaced?

S.Y., Minneapolis

A: If this were a simple trim piece, we would let it go, but the splash shield on the front underside of the car has several purposes, including protecting the engine from bumps and road debris, so we would replace it. If you are handy, and can safely get under the car, you can install a replacement for under $40. To have a pro do it, expect to pay more for the part plus labor, which should be about one hour.

Q: I own a 2009 Pontiac G6 with the 3.9-liter engine. It now has 94,000 miles on it, nearly all highway miles. I had no intention of keeping this car so long as I used conventional motor oil. I would like to know your thoughts on switching over to synthetic at this time. I am thinking that I would like to keep the car another 100,000 miles. What do you think?

M.M. Aurora, Ill.

A: Synthetic motor oil is superior to conventional dinosaur juice. And it is never too late to make the switch. You may want to consider a synthetic blend that contains both types, as well as an oil designed for use in higher-mileage engines. We believe any car can go over 200,000 miles if maintained properly.

Q: I bought a 2016 Lincoln MKC in November 2015. Recently hot air was blowing on the driver's side when the air conditioner was on. When I called the dealer to get it fixed under the warranty, I was told I had to wait two weeks. The Lincoln brochure says: "Should your Lincoln require warranty service, you can count on us to be there for you with a courtesy vehicle. It's just one more way to let you know that we'll be there for you." I inquired about the courtesy car but was turned down by the dealer and the Lincoln people (who said) the car had to be in the shop to get the courtesy car. So I would have to drive my car without air conditioning until then. I got the car fixed by someone else. Are there luxury carmakers that would have provided the courtesy car until they could fix the problem?

P.M., Chicago

A: If car dealers had to supply courtesy vehicles while waiting for an opening in the service schedule or waiting for parts to arrive, they would go broke supplying loaners. That is why many dealers co-op with rental agencies such as Enterprise. Think, for a moment, how many cars the dealers would have to lend out just for recalls awaiting airbags. While the car is in the shop, many dealers happily provide a courtesy car for a couple of days.

Bob Weber is a writer and mechanic who became an ASE-certified Master Automobile Technician in 1976. He maintains this status by seeking certification every five years. Weber's work appears in professional trade magazines and other consumer publications. His writing also appears in automotive trade publications, Consumer Guide and Consumers Digest. Send automotive questions along with name and town to