I don’t usually make comments on products but I recently ran into an unexpected problem with my 2011 Silverado 5.3 L V8 with Flexfuel. It consumed over 3 quarts of oil in a 5,000 mile oil change period. I talked to the GM shop foreman and he told me the 5.3 was notorious for that and I would need an engine rebuild or replacement. ….. My fix was to change the driver’s side valve cover to replace the PVC, took out the new 5/30 weight oil and replaced it with synthetic oil. I installed the new Range OBDII plug in and holy cow! My engine response is fabulous, I have gained nearly two miles per gallon on the fuel efficiency and in 2500 miles haven’t used a quart of oil. For the money, for any money, it is the best fix for anyone with a GM 5.3L V8 with the Flexfuel design. GM should offer one to anyone with the problem of oil consumption in lieu of trying to upsell to a newer vehicle. Thank you all for your technology!