Improved lubricants have allowed service intervals to extend for many vehicles with automatic transmissions, utilizing “lifetime fluids.” In the past, service recommendations for automatic transmissions were based on time/mileage tied to requirements of new vehicle warranties (2-3 years or 30,000 miles). Lifetime fluid recommendations are now 5-10 years or the life of the vehicle (100,000 miles) unless the vehicle is subjected to “severe duty.”

The question that often comes up next: When is it appropriate to perform a fluid service? Taken directly from OEM owners’ manuals, “severe duty” has historically been defined as:

• Operation of vehicle when ambient temperature is above 100° F. or below 0° F.

• Carrying heavy loads or multiple passengers on a daily basis.

• High speed highway or interstate driving for extended periods of time.

• Driving in hilly or mountainous areas.

• Stop and go driving.

By definition, most drivers are engaged in severe duty vehicle operation most of the time. The severity and non-stop cold weather of this recent winter is a perfect example of severe duty conditions that really stress and deteriorate all of the lubricants in a vehicle. The standard recommendation is to cut the recommended change interval (30,000 – 100,000 miles) in half and perform service based on severe duty (15,000 – 50,000 miles).

Most drivers are looking to minimize the cost of ownership and still meet the warranty requirements. Most warranties clearly state that failure to perform routine maintenance will void the warranty. When we service vehicles, we owe it to our customers to qualify their driving habits. We need to show them if they operate their vehicle in a manner that may require a more frequent service cycle. When we provide the customer with the advice and service they need to maintain their vehicle and OE warranty based on real world considerations, we instill trust, confidence and loyalty.