Bowtie Billy Hill

Is that where the V8/V4 squeak came from? I had a '14 that did it from day 1. I never really put any thought into what was causing it. I learned something new today. What is the purpose of the exhaust flap anyways? Sent from my D6708 using Tapatalk

I've had (allegedly) three Silverados with 5.3 AFM engines. I say allegedly because my '08 had AFM listed on the window sticker, but that's as close as I ever came to it. I don't believe the AFM ever kicked in on that truck in the three years that I had it, and I averaged about 13.5 mpg all the time with it. My '14 had the newer 5.3, which is a whole different animal than the engine in my '08. I just turned it in with 30k miles on it, and AFM never caused me a single issue. It did, however, help me average roughly 16 mpg running the same route everyday that I did in my '08. I'm not going to argue with 2.5-3 mpg more. The 4/8 cylinder transition was smooth in that truck, and I was the only one who could pick up on a very quiet chirp that it would make going back into 8 cylinder mode...and only if it was quiet in the truck. My new '17 has the exact same setup. The transitions seem even smoother, and the AFM seems to activate even easier in this truck. I'm already averaging about a half mpg more in the new truck under identical conditions, and it only has 650 miles on it. No tiny chirp in this one, either. I've never used a drop of oil in any of my trucks, or had any AFM related issues. Go for it, and warranty the crap out of it if you would happen to get a bad one.

That's the only problem I ever had with my '14 the whole time I had it. Service 4wd message came on, and it wouldn't shift out of 2wd no matter where the knob was turned. At least I was stuck in 2wd. Could've been worse. Seems to be fairly common, though. I had the exact same problem years ago with my '03 ZR2 Blazer.