How often do you change your air filter? Or how often do you clean your air filter? Such a simple thing that people often overlook when they bring their vehicle in for a tune. We took a stock 2500HD GM truck and set it up to do some testing for you. Testing the one-year old air filter against the brand-new air filter, versus cleaning the old air filter. As expected, their results told us what we should do.

First, we loaded the truck on the dyno and got it warmed up and made 3 runs, all averaging out just fine at 280whp and 306wtq. Not too bad for a daily driver of a truck. You can see this as the red run on the dyno graph. Nice smooth power and someone could be happy with this. However, the truck has not been serviced, besides oil changes, in a year. So why not change out the 20,000-mile old air filter? How harmful can it be anyway?

Well, this is where we moved on to test the same truck, same heat, same day, same everything, but simply changing the air filter. We got a new OEM replacement from the local parts store and made a few runs. Averaging out to be 292whp and 313wtq. You can see solid gains in the blue run over the initial red, old air filter run, being all we did was general maintenance. Something that should have been done anyway. But let’s carry on and do one more thing we all have done before, blow the air filter out.

After blowing the OLD air filter as clean as we could, we tossed it back in and tested it. Now, I am a not a fan of doing this, as you can end up just pressing what dirt was on the filter into the paper of these OEM filters more, but hey, it's worth a shot! After three runs we averaged out better than I figured. Take a look at the black run on the graph, you can see we only lost a little compared to the new air filter. Truly, this is within dyno error I would say.  Ending up at 289whp and 310wtq. Honestly, this surprised me, I figured it would be worse.

Simple things you can do here guys… just maintain the vehicle. A fresh tune-up goes a long way, as we expected, but here’s a simple “just further the proof” for you. If the vehicle is on your dyno, offer the service. Customers typically won’t say no to a higher power output, which doesn’t end there. That means the engine will get better overall efficiency which obviously leads to better fuel mileage. Be their hero, change an air filter, and make a few bucks doing it.