The Pros and Cons of Switching Oil
Q. My wife has a 2007 Lexus IS250 which we have been running on conventional motor oil. Recently, my mechanic suggested switching to synthetic. What do you think? Are there pros and cons for switching older cars onto synthetic oil? Also, I’ve heard that if you do switch to synthetic oil you should not switch back and forth to conventional oil. Is this true?
A. The advantages of synthetic oil are, longer oil change intervals, improved lubrication and in some cases a very slight improvement in fuel economy. The disadvantages are cost; synthetic oil can cost two to three times that of conventional oil. Using my wife’s car as an example with conventional oil I was changing the oil four times per year. With synthetic oil I change the oil twice so in this case the costs are very similar. Regarding problems with changing back and forth from conventional to synthetic this is nothing more than a myth.
Q. I have a BMW X3 with about 65,000 miles on it. Recently the dealer changed oil and noticed that the left rear coil spring was “broken’’. I spoke to service advisor and mentioned that I have not noticed any difference in the way the car handles and was surprised that a coil spring would break in less than 5 years with only 65,000. She said perhaps it was not “broken’’ but “cracked’’ and about to break. Again, we have not noticed any difference in the way car takes bumps and how it handles. What is your opinion and should I replace right now?
A. If the spring is broken it needs replacing and actually both rear springs should be replaced. Regarding not noticing any difference in how the car handles, In a busy repair shop it is not unusual to see a car go on a lift for inspection only to see a piece of the spring fall out and the owner of the car never knew there was a problem. At this point I would get a second opinion just to be sure.
Q. My 2007 Honda Accord with 48,000 miles started to twitch during the mild acceleration-generally under 2000 RPM. I can feel a kind of light shaking in the engine compartment. If I press the gas pedal hard, it disappears. I have recently replaced air filter hoping to fix it – no change.
A. I would start with a basic checkup. The issue you are having could be as simple as a vacuum leak causing a slight lean engine misfire. In addition if the EGR (exhaust gas recirculation) valve is opening a bit too early this could also give you the same feeling. Both of these items could happen without setting a check engine light.
Q. I’m considering purchasing a new Toyota. To save money, do you have any idea if I can have buy one overseas and have it shipped to Massachusetts?
A. Some car companies have European/US delivery programs. These programs may not save you a lot of money but will allow you to drive a car in Europe for while on vacation then ship the car back home. The second issue has to do with how the US dollar is fairing against other currencies. Currently you could buy a US specification car overseas and have it shipped here but there would be no saving since the car is made here as well. These programs tend to be more advantages with BMW and Mercedes as opposed to Toyota.
Q. I have a 2002 Lexus RX300 with 130,000 miles. About six months ago, I replaced the battery. Occasionally, when I start the car, if I don’t keep my foot on the gas for a minute or so, it stalls. I have to rev the engine for a minute or two before I can put it into gear. I’d say 99 percent of the time it starts no problem, but every so often I get this problem. Could it be just an old and cold engine or is it a bigger problem?
A. The first place I would start is with a complete cleaning if the air/fuel intake system. If the throttle plate has carbon build up the car will stall or run rough during a cold start. This is a simple and generally cost effective repair.
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