Subject: 2006 Silverado Duramax HD2500. I was getting tired of waiting for the gauge on the filter housing to say filter needs replacing, so I installed an very low restriction racing filter. It's supposed to be less restrictive than a K & N filter. Here's what is happening: Previously when I filled the tank and reset the odometer the DIC would show mileage counting down from very high to low mpg and of course the mpg average would slow down with more and more mileage. Now (after new filter installed) the same procedure shows mileage going up from near zero to less economy then with the old filter. Is there some sort of parameter to change in the cpu for a low restriction filter I never experienced any problems installing a performance air filter in dozens of vehicles of all types any time in the past. Any ideas? or just get another OEM filter replacement - if you could see how restrictive and tight these oe filters are! and PS: now I have a "Check engine" light on. I need to get this truck inspected tomorrow so in the morning I'll check with my handy-dandy reader.