Changing your oil and filter often is critical to protecting your engine from premature wear and viscosity breakdown.

How often should oil and filter be changed?

For most cars and light trucks, the standard recommendation is to change oil and filter every three months or 3,000 miles whichever comes first.

Most late model owner’s manuals say except for “severe service” applications, oil change intervals can be stretched to once a year or every 7,500 miles, with filter changes at every other oil change.

Except for Chrysler’s 7/70 powertrain warranty, and a few others that go up to 5/50 or 6/60, most new car powertrain warranties don’t go beyond 3/36. So where’s the risk? Your vehicle will be out of warranty soon after you drove off the dealer’s lot and the manufacturer won’t be responsible and damage do to lack of oil changes.

With proper auto maintenance, there is no reason an engine shouldn’t go 100,000 miles or more with out developing a thirst for oil. That is why most oil companies, as well as aftermarket service professionals recommend changing your oil every three months or 3,000 miles. Severe service (as defined by the auto makers themselves) includes:

  • Making frequent short trips (less than five miles)
  • Making frequent short trips (less than 10 miles) when temperatures are below freezing
  • Driving in hot weather stop-and-go traffic
  • Extensive idling and/or low speed driving for long periods of time (taxi, police, door-to-door delivery, etc)
  • Driving at sustained high speeds during hot weather
  • Towing a trailer and/or carrying heavy loads
  • Driving in areas with heavy dust (gravel roads, construction zones, etc)

The protective additives in motor oil do not hold up as well under such driving conditions for several reasons. If the engine is not running long enough to get the oil hot, condensation and fuel vapors will not boil off. Contaminants will accumulate in the crankcase, leading to formation of corrosive acids and sludge.

Excessive idling and high operating temperatures from towing and high speed driving during hot weather accelerate viscosity breakdown. Exposure to dust can put dirt particles in the crankcase.