If every 7,500-mile maintenance worked in the past, why change it? | Car Doctor
Q: I recently purchased an almost-new 2019 Subaru Outback (3.6 engine). I was disappointed to learn that the maintenance schedule was shortened by 1,500 miles from my previous 2013 Subaru Legacy (2.5 engine). The new car requires maintenance at 6,000 miles and the older car at 7,500.
Historically, the maintenance intervals have only been growing, probably due to better-built engines and improvements in motor oils. This really has me scratching my head. A skeptic (such as I) may wonder if there is a logical/valid reason for this decline or whether it is simply a ploy to drum up more business for the dealerships. This reduction also applies to tire rotations (and all other items on the maintenance schedule). If every 7,500 miles worked in the past, then why change it? I sure would appreciate some enlightenment.
A: I think you may be on to the answer. The 7,500-mile schedule may not have worked in the past as well as the manufacturer hoped. All vehicles use oil, and it may be that consumers were not checking the fluids as often as they should have.
It appears that Subaru changed to 6,000-mile intervals in 2016, hoping to get vehicles in for service more often to prevent damage to vital engine parts.
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Tricks to remove a rounded-off lug nut
Q: I had a flat tire, and one of the lug nuts is severely rounded and I could not get it off. I tried all the usual things to get it off with no luck. I ended up having the car towed to a repair shop, where they torched off the lug nut. Was there something else I could have tried before the expense of towing and replacing the stud and lug nut?
A: The usual trick is to take a slightly smaller metric six-point socket and force it over the rounded-off lug nut. Depending on the condition of the lug nut, a 12-point metric socket might also bite into the damaged lug nut. The best method to force the socket on is to put it on a breaker bar (to protect your fingers) and drive it on with a large hammer. You can also buy or borrow a lug nut removal tool from an auto parts store. These special tools are designed to bite into the lug nut and are grip more tightly the more you turn.
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Coaxing a long-dormant car out of hibernation
Q: I have an old car that has not been running in years, and I want to get it going. So far, I have charged the battery, and it has spark and fuel, but it still will not start. Any ideas?
A: Someone recently asked me to look at a car that also has not run in a while. Like your car, the battery was OK, there was a spark at the plugs, but the car would not fire up, even with starting spray. I pulled the spark plugs and they were somewhat fouled, which certainly would cause hard starting.
I asked how long it had been parked. The answer shocked me: The owner thought five years or so. The problem was a combination of fouled spark plugs and gasoline that had gone stale.
Flushing the gas tank and replacing the fuel pump and the spark plugs made this old car run — not quite like new, but at least it ran.
The lesson to be learned here is even gasoline with a fuel additive will eventually get stale. When a car is stored for longer periods, there are additional measures that need to be taken to ensure the engine will run again when it comes out of hibernation.
Now, having the car running is only part of the equation. You also need to look at the brakes, all fluids, steering and suspension, electrical issues and the radiator and cooling system. Too often people will start up an old car and immediately take it for a ride, only to find that it overheats and the brakes do not work.
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Q: I drive a 2013 Honda Accord that only has 75,000 miles on it. Can you tell me if I am damaging or incurring excess wear on my transmission by shifting down and letting the engine do the braking rather than using (and saving) the brakes?
A: It is much cheaper and more efficient to use the brakes to slow the car rather than the transmission. The internal bands and clutches of an automatic transmission in your 10-year-old car are not designed for continuous manual downshifting.
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John Paul is the AAA Northeast Car Doctor. He has more than 40 years of experience in the automobile industry and is an ASE-Certified Master Technician. Write to John Paul, The Car Doctor, at 110 Royal Little Drive, Providence, RI 02904. Or email jpaul@aaanortheast.com and put “Car Doctor” in the subject field. Follow him on Twitter @johnfpaul or on Facebook.
This article originally appeared on The Providence Journal: Why did Subaru change maintenance schedule to 6,000 miles?: Car Doctor
