Truck Engines are so much different than car engine and that goes for the Air Cleaners too. An air filter on a semi-truck must take in huge volumes of air. Any dirt or debris that gets into the engine through the air-filter can damage the engine and it does not take very much either. In fact 8 to 10 ounces of dirt can literally destroy a $20,000 to $40,000 motor. Most people do not realize how much air moves through the air-cleaner of a Diesel Truck Motor, it is tremendous amount of air that needs to be cleaned to insure proper burn and performance. Truck air filters are very nearly 100% efficient and they have to be to protect the motor. When the air flow comes into the filter the air comes through and the dirt is trapped as it sticks to the air-filter, which is the first line of defense for the air-cleaner system. The dirt sticks to the filter and to other dirt which has already been trapped there. This is why a clean air filter is not as useful as an air filter, which is a little dirty.Proper air cleaner strategies increase engine efficiency, meaning less pollution, more power and better fuel economy. For Diesel Truck Oil and Lube Companies and locations they need to understand that if they are advising truck owners to change the air-filter after each oil change they are actually cheating their customers and lessening the life of their truck engines, because a little dirt on the filter helps collect other dirt that is in the air flow being sucked in.Awareness of air-filter issues are a smart step to increasing fuel economy whether the motor is running Bio-Diesel, Straight Diesel or Hybrid Diesel notes the T-5 Group (The Truck Technology Think Tank Team). In fact some manufacturers claim that their OEM truck filters can operate for over 120,000 miles prior to change out.