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Why does the manufacturer say transmission fluid is good for the life of the vehicle?
John Paul, AAA Northeast's Car Doctor, answers a question from a reader who was told they never had to change their vehicle’s transmission fluid.
Q. I have a 2016 Mazda CX-5 with 115,000 miles. It runs like new with coolant, brake, and trans axle fluid changes as well as numerous engine oil changes. What baffles me is that Mazda does not recommend transmission fluid/filter changes. They say it is good for the life of the car. Your thoughts on this and what exactly should be done? A simple fluid drain and refill, pan dropped and cleaned with a new filter, or complete flush? What should I be paying for this service?
A. Always an interesting question when the manufacturer says lifetime fluid. As an example, BMW lists the transmission fluid as a lifetime fill, but the transmission manufacturers state the fluid should be changed every 60,000 miles. I think it is a good idea to change the fluid (drain and refill) depending on how you drive. If you tow a trailer, drive for ride hailing, or part time deliveries, I would change the fluid every 50-60,000 miles. If you drive nice and easy, perhaps you can go much longer. As for cost, I would only use Mazda fluid at $10-$20 per quart with about five quarts needed. Expect about an hour of labor for the service. I would avoid a transmission flush and stay with a drain and refill.
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Q. I have had to jumpstart my car eight times this week and it is only Thursday. This eighth time before I could leave my office, AAA had to come out and jump it for me because my jumper kit had run out of battery from jumping the car on average twice a day for the past three weeks. My current battery is only 13 months old, and I turn off the headlights, radio, and unplug any chargers from the car every time I turn it off. What more can I do to ensure I have a reliable car? It’s a 2015 Honda CR-V.
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A. Although the battery may have an issue now (you can only jumpstart a battery so many times), at some point the battery needs to be charged with a battery charger and then tested. From your description, it sounds like your car has a parasitic drain. Some components are not shutting down and that is draining the battery. Common issues are defective relays, the hood latch, and the driver’s door handle, which can cause courtesy lights to come on. At this point the car needs to have the battery charged, alternator tested for output, and then a test for parasitic drain. The shop may need the car for more than one day to test the electronics.
Q. I have a question about trading in my 2019 Subaru Outback. Carvana offered a $11,600 trade in, sight unseen. If they see something they don’t like, can they drop that price? And if so, would I still be obligated?
A. Carvana claims you can get a real offer in two minutes. You can trade in the car or sell it to them 100 percent online. In Carvana’s words “No haggling, no headaches.” A neighbor of mine wanted to trade in his Ford F-150 for the smaller Ford Ranger. The local Ford dealer offered $19,000 for a trade, Carvana offered $23,000. He was prepared to take the Carvana offer, and the local dealer stepped up and matched the price. So Carvana can make it easy to sell your car or use their price as a negotiating tool.
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Q. I still listen to AM radio and lately the reception is not good. What can I do to improve the radio reception back to when the car was new?
A. The most common issue is a bad ground with the antenna. As rust builds up under the antenna mount this can cause electrical noise, introducing static and interference into the radio signal. Start with checking the antenna and if possible clean up the mounting area. Also check any chassis ground cables for green corrosion.
Q. Have you ever tested out the Harbor Freight ICON scan tools? I’m about five years into working as a tech and although our shop has a Snap-on scan tool, sometimes others are using it. In the meantime, I purchased an Innova 5610 scan tool and it does pretty well, but I was looking for something better.
A. The Innova 5610 is a good tool and with bi-directional controls can handle many tasks. I recently have been using the Harbor Freight ICON T-10 and it is very impressive. There are sub-menus listed that I did not see on much more expensive tools. Not cheap, but it also comes with a battery tester and borescope. The borescope with the large tablet display is very nice. Everything from the unit itself, charging dock, to cables, to the quality case put it in the professional scan tool category.
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Q. I have noticed I use only the metric sockets when working on my car. Is it safe to donate or sell the SAE sockets?
A. Although your car may use metric sockets, sometimes working around the house you will need SAE sizes. I have an old Honda push mower that was given to me, and the Honda engine is metric, but the deck bolts are all SAE sizes. When I quit being a working mechanic, I kept SAE sockets and wrenches and donated more specialized tools, large sockets, pullers, air tools and testers to the local vocational school.
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 Doctor question to [email protected]. Listen to the Car Doctor podcast at johnfpaul.podbean.com.
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