Oil change

Most vehicle manufacturers recommend changing the oil once a year or every 7,500 miles in passenger car and light truck gasoline engines. For diesel engines and turbocharged gasoline engines, the usual recommendation is every 3,000 miles or six months.

If you read the fine print, however, you’ll discover that the once a year, 7,500 mile oil change is for vehicles that are driven under ideal circumstances. What most of us think of as "normal" driving is actually "severe service" driving. This includes frequent short trips (less than 10 miles, especially during cold weather), stop-and-go city traffic driving, driving in dusty conditions (gravel roads, etc.), and driving at sustained highway speeds during hot weather. For this type of driving, which is actually "severe service: driving, the recommendation is to change the oil every 3,000 miles or six months.

For maximum protection, most oil companies say to change the oil every 3,000 miles or three to six months regardless of what type of driving you do.

A new engine with little or no wear can probably get by on 7,500 mile oil changes. But as an engine accumulates miles, blowby increases. This dumps more unburned fuel into the crankcase which dilutes the oil. This causes the oil to break down. So if the oil isn’t changed often enough, you can end up with accelerated wear and all the engine problems that come with it (loss of performance and fuel economy, and increased emissions and oil consumption).

Oil Analysis

Truck fleets often monitor the condition of the oil in their vehicles by having samples analyzed periodically. Oil samples are sent to a laboratory that then analyzes the oil’s viscosity and acid content. Oil is then burned in a device called a spectrometer that reveals various impurities in the oil. From all of this, a detailed report is generated that reveals the true condition of the oil.

Oil analysis is a great idea for fleets and trucks that hold a lot of oil. But most consumers would have a hard time justifying the cost. Having an oil sample analyzed typically costs $12 to $20 for the lab work and report. Most quick lube shops charge $16.95 to $19.95 for an oil change. So why spend your money on a report that will probably tell you your oil needs changing? Just change the oil every 3,000 miles and don’t worry about it.

Regular oil changes for preventative maintenance are cheap insurance against engine wear, and will always save you money in the long run if you keep a car for more than three or four years. It’s very uncommon to see an engine that has been well maintained with regular oil changes develop major bearing, ring, cam or valve problems under 100,000 miles.

More information at: http://www.mostvaluabletips.com/autos/car-maintenance/oil-change.html