Car Maintenance 1Dear Ole Mechanic;

What is considered normal maintenance for a car or pickup?  I see commercials that say to change the oil every 3,000 miles, yet my owner's manual says to change it every 7,500 miles.  Can you explain?

Mrs. I. M. Confused

Dear Mrs. Confused;

I would like to congratulate you for reading your owners manual, but I am going to suggest that you read it a more closely.  I know that reading the owner's manual is not exciting reading; in fact, it rates right along side of watching paint dry.  Usually, right after the oil-change recommendation, the manual will list a number of exceptions.  Those exceptions include trailer towing, short trips under five miles, extremely cold weather, extremely hot weather, long periods of idling and dusty conditions.  If any of these exceptions apply to your driving, then the manual will probably recommend more frequent oil changes, and most will recommend changing the oil every 3,000 miles or three months, whichever comes first.  Of the exceptions listed above, the most harmful to your car's engine are short trips.  It is a fact that more engine wear occurs in the first five minutes of running than will occur in the next five hours of running.  The reason for this is that when a cold engine is started, it takes a while for the cold oil to reach all of the moving parts that need lubrication.  That is why it is a good idea to warm up the car/s  engine for a minute or two before starting to drive it.  But don’t think that just because the heater is starting to put out heat that the engine oil is warmed up also, because it is not.  It can take up to 10 miles or more of driving for the oil to reach operating temperature.  This even applies in the summer, too, because even though the air temperature is 100 degrees, the operating temperature for the engine coolant is around 190 to 200 degrees.  The operating temperature for the engine oil is over 212 degrees.  Why is the operating temperature for oil so hot?  To boil any condensation and moisture out of the oil to prevent sludge and other contaminates from collecting in the engine.  Short trips cause the engine to warm up some and then cool off, allowing moisture to condense inside the engine.  To get rid of the moisture and other contaminates, you drain them out with the oil when it gets changed.  So if your driving includes short trips to the post office, change your oil every 3000 miles or three months--whichever comes first.  Even if you do not make short trips, remember that the dusty conditions exception applies to our part of the world, so an oil change every 3,000 mile or 3 months is recommended.  You have probably noticed that I have not said anything about the oil filter.  Herr Professor does not like to leave a filter full of old and possibly contaminated oil to be mixed with clean fresh oil being put into the engine.  I change the filter every time I change the oil, as filters are not that expensive when compared to a new engine. 

Car Maintenance 1So  far all I have covered is the oil, but there are a lot of other things involved with normal maintenance.  Yes, there is the traditional “lube job” that is part of the normal “lube, oil and filter for $29.95.”  In the past, that lube job included greasing 20 to 30 normal wear areas under the car and lubricating other wear areas like door and hood hinges and things, as well as checking the transmission and axle lubricant levels.  Today’s cars have plastic bushings in hinges and many sealed components.  There may only be six or fewer grease zerks (fittings) underneath and little else to service except a cars transaxle or the transmission/rear axle lubricant levels and other fluid checks.  But even that is not all that is needed for normal maintenance.  There are many other things that need attention or checking, such as the air filter, brake fluid and brake wear, tire inflation, rotation and wear, light bulb, battery-cable connectors, fan-belt condition and age, fuel-filter replacement--the list goes on and on.  The reason that I am not going to list everything is that I would probably forget something and some things that apply to pickups, such as wheel bearing packing, do not apply to most front-wheel drive cars as they have sealed bearings.  Your owner's manual will do a better job of covering maintenance items for your car than I can do in this article.  There is one thing that I am going to suggest (and I am not the first to suggest this) and that is that mechanics are like Doctors--if you find a good one, then hang on to him or her.  There is a good reason that I recommend finding a good mechanic.  That is because a mechanic is accustomed to problems that can occur and can do one of the most important maintenance items very easily--a good visual inspection.  You can help with this by looking for fresh drips from under your car or truck on the driveway, looking at the tires when you check the tire pressures and looking for leaks while checking the oil level between oil changes.  Now if you are not familiar with the things that I just mentioned, then I would suggest that you look into the continuing-education classes offered by area schools and take an auto-familiarization class.  Either that or join a auto club like AAA or get a cell phone and put your mechanic's phone number on the speed dial.

Herr Professor Nuzanbolts