Anybody use or have firsthand lowdown on the OBDII plugin devices that turn off the VVT nonsense on GM 5.3 (and other) GM V-8's? I have a 2013 Silverado with the 5.3- I haven't dropped a lifter or had catastrophic failure yet, but I'm starting to burn or lose almost 2 quarts between oil changes.
From what I've read, they really don't effect fuel mileage, and it won't help the oil loss- but it may keep it from getting much worse. Anybody have anything good, bad, or ugly to say about these plugin modules? Thanks in advance.

You can turn off afm in the dic on each startup.

You can have it programmed to never engage by a performance tuner.

You can also install a pcv circuit oil catch can and improve your combustion by preventing blowby from returning.

Use Valvoline Restore and Protect engine oil to remove internal engine deposits and free the piston rings that are likely stuck. Your symptoms suggest stuck rings.

You may be conflating two issues. Stuck piston rings cause problems. AFM causes different problems. Fix both.

I have use the OBD plug in from Range Tech in two Suburbans a 2010 and a 2016 with great results.

https://www.rangetechnology.com/

4MUL8R,I have a 2014 Silverado and would appreciate any info where in the dic to look for the ability to turn off the AFM programming. To my best knowledge it cannot be disabled unless its you use one of the Range products or have someone tune it out.
I too have used a Range Tech plug in with no problems.

Thanks, Greg

My dad had a tuner disable it on his 2012 6.2 Denali XL
My father-in-law just got one of the OBD disablers, but I don't recall which, wasn't the Range posted above. Hasn't had it on long enough to notice any appreciable difference.

I used the Range device on a 2015 Yukon XL with the 6.2. Put it in when we purchased it used with aroound 40,000 miles. No issues whatsoever with the device and any difference in fuel mileage wasn't noticable.

All of that said it still started using 2+ quarts of oil about every 3000 miles with 140,000 on the clock. We got rid of it shortly after it started the excessive oil consumption.

I used the Range in my 2010 Silverado. I plug it in about a year after I purchased the truck, worked great.
Depending on the mileage on your truck, it may or may not be worth it.

I use one in a 2009 GMC Z-71 Sierra with a 5.3L. I bought the truck used in 2018 with 152K miles. I put a Range Technologies AFM delete plug-in on it within a month of purchase. I now have 198K miles with no issues using it.

I will say, every so often, the Check Engine Light (CEL) will appear after startup. I remove the AFM module, wait a few seconds, then plug it back in. Within 25 -30 seconds, the CEL turns off. On the RT website, I found that the OBD system in the truck treats anything plugged into the OBD port as a test device, and counts start cycles. After a certain number of those, the CEL illuminates as a "reminder" to remove the test device. Removing and re-installing the AFM delete module resets the start cycle count. A minor inconvenience, but no affects to the operation of the AFM delete module.

Good luck.