Q. I own a 2018 Mercedes Benz and recently I noticed that the highway exit numbers have changed. My question is, would an update to the factory GPS be covered under my warranty?
A. Exit numbers are changing to comply with a mandate from the Federal Highway Administration for all states to have exit numbers match mile markers. This method will allow motorists to know the distance between exits or the miles to a destination. In addition, it should be easier to locate motorists if they break down. The old numbers are required to be posted for two years after the exit number has been updated. Since the navigation system is operating as it was designed it would not be covered under the warranty. I recently evaluated a 2021 Mercedes Benz GLC and the navigation system in this brand-new vehicle had the old exit numbers. At this point all you can do is contact Mercedes Benz customer care and ask about an upgrade to the software.
Q. I have been watching car auctions on televisions and all the cars look great. Would you ever buy a car from an online auction? I really would like a mid-60’s pickup truck and many cross the auctions. I recently saw an auction of an entire museum out of Florida and the cars and trucks looked outstanding.
A. People buy vehicles at online auctions all the time, and as long as you have an idea what you are getting and where it’s coming from, I think you are generally not taking too much of a chance. I understand the idea of an antique pickup truck, especially from the 1960’s that is old enough to be fun, but useful enough to go to the home improvement store. I think the auction you may have seen was the Muscle Car Auction out of Florida. I visited that museum in Punta Gorda, and many of the vehicles were nearly perfect. That being said, they were set up for a museum environment, and I’m sure at the least, the fuel systems, cooling systems, and brake systems would need refreshing.
Q. I have a 2010 Mazda 3, and the rear shock mount broke. My question is should I replace both rear mounts? The car has fairly low miles for its age and I do plan on keeping it for a while.
A. The mount is actually part of the rear shock, so in this case, since the car is 11 years old, replacing both shocks would be money well spent. At the same time, it would be a good idea to give the car a thorough undercarriage inspection just to make sure there are no structural issues that you need to be concerned about.
Q. I was going through the garage at my dad’s house and found a case of 20W-50 Castrol oil. The case was never opened and the cans (yes cans and even a spout) are in good shape. I remember this was the oil that we used in all of our vehicles when I was a kid. We even used it in my motorcycle. Can I still use this oil?
A. I get this question periodically. The oil you have is at least 30 years old. Today’s engines require more sophisticated oil with specific additives. You are better off trying to sell or trade the oil to an oil can collector. I looked on eBay and Castrol GTX 20W-50 oil had starting bids of $8 or more per can. If you can get close to that per can, you can pay for the proper oil (and even upgrade to synthetic oil) for your newer vehicles.
Q. I have a Jeep and the battery was going dead. I found that for whatever reason the radio was staying on. I looked at the wiring and plugs, and finally just unplugged the radio. With COVID, I don’t drive much, but driving without a radio, especially in a Jeep, is painful. Any ideas?
A. Depending on the age, some 2002-2008 Jeeps were prone to an internal shorting of the ignition switch. When this happens, even with the key off, power is still supplied to some accessory circuits. Testing the connections from the ignition switch should confirm the problem.
John Paul is AAA Northeast’s Car Doctor. He has over 40 years of experience in the automotive business and is an ASE-certified master technician. E-mail your car question to [email protected]. Listen to Car Doctor on the radio at 10 a.m. every Saturday on 104.9 FM or online at northshore1049.com.
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