You can deactivate it. I have a friend who did this on his silverado. The bigger issue is the fact that those junky lifters are still in there. I have this feature on my 12' silverado, and even though it helps out on mileage, I'd love to do the swap (cam, lifters, valley cover), just to ensure that the DOD (AFM) lifters don't come apart and tear up a perfectly good engine. Lots of them do.
Brian Hobaugh SCCA National Tour June 2014
First Hemi 'Cuda Convertible Ever Built
Short clips: Goodguys Pleasanton autocross and pit videos
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