Dayton Daily News

Halderman: This is the last of a five-part series on engine oil.

Oil change intervals

All vehicle and engine manufacturers recommend a maximum oil change interval. The recommended intervals are almost always expressed in terms of mileage or elapsed time (or hours of operation), whichever milestone is reached first.

Most vehicle manufacturers recommend an oil change interval of 7,500 to 12,000 miles (12,000 to 19,000 kilometers) or every six months. If, however, any one of the conditions on the following list exists, the oil change interval recommendation drops to a more reasonable 3,000 to 5,000 miles (4,800 to 8,000 kilometers) or every three to six months. The important thing to remember is that these are recommended maximum intervals, and they should be shortened substantially if any of the following operating conditions exist.

1. Operating in dusty areas

2. Towing a trailer

3. Short-trip driving, especially during cold weather (The definition of a short trip varies among manufacturers, but it is usually defined as
4 to 15 miles (6 to 24 kilometers) each time the engine is started.)

4. Operating in temperatures below freezing (32 degrees F, 0 degrees C)

5. Operating at idle speed for extended periods of time (such as normally occurs in police or taxi service)

Because most vehicles driven during cold weather are driven on short trips, most technicians and automotive experts recommend changing the oil every 3,000 to 5,000 miles or every three to six months, whichever occurs first.

Follow the seasons

Vehicle owners often forget when they last changed the oil. This is particularly true of the person who owns or is responsible for several vehicles. A helpful method for remembering when the oil should be changed is to change the oil at the start of each season of the year.

Fall (Sept. 21)

Winter (Dec. 21)

Spring (March 21)

Summer (June 21)

Remembering that the oil needs to be changed on these dates helps owners budget for the expense and the time needed. If the vehicle manufacturer recommends that the oil be changed every six months, then try to select times that can be easily remembered. For example, I change the oil in both vehicles twice a year in December and June.

James D. Halderman is an ASE-certified master technician, a member of the Society of Automotive Engineers and the author of 12 textbooks. Submit your automotive care questions to Halderman via e-mail at jhalderman2@juno.com, or write him in care of: Wheels, Marketing Publications Department, Dayton Daily News, 45 S. Ludlow St., Dayton OH 45402.