Elk

^^^

Every issue is blown out of proportion on the forums. It is how the Internet works, unfortunately.

jwmgr8

A few comments/opinions:
1. I do not like AFM for a Corvette. I did not buy a V8 to run on only half the cyl. The system created to allow the engine to run on 4Cyl. is very complex. I like less complex, unless there is a really big benefit. I do not like the cars/trucks that cut the engine at stop lights? again it is a complex issue. Todays engines are already pretty dare complex getting the power and reducing emissions.
2. I find it interesting when folks talk about stuff getting blown out of proportion. I find that if something happens to you directly it becomes important. If something happens to others it just something to say it is being blown out of proportion?
3. I like the forum for many reasons but it is important that when sharing issues, be factual. If asking for help or opinion, be precise. If sharing opinion say so. The pictures provided are great. There is unlimited amount of creativity out there and the forum is a great place to share.

Have fun, drive safe

Elk

As expressed by the OP in his first post, this is not the thread for pronouncements "I didn't buy a Corvette to run on 4 cylinders." Nor is this the thread for complaints about AFM - there are dozens already for this.

Chemdawg99

Never used the Range device in my 2016 and had no problems related to AFM with over 66,000 miles on the odometer.

Tried the Range on my 2019, but didn't like the gas mileage hit and removed it never to be used again. No problems related to AFM on my 2019 with over 12,000 miles. Have a 2009 Chevy Avalanche with AFM. Never had any problems related to AFM with 130,000 miles on the clock.

As has been said, people come here to post their problems and to sing the praises of their solutions to their problems (real or perceived). The Range works as advertised, but I'd rather err on the side of making sure my warranty is intact (still on factory warranty which I extended upon buying my car new last year) vs. worrying about what GM designed the car to do. I never know when the car is in V4 mode because the transition is imperceptible and seamless. This is not to say that problems related to it don't exist, but I have never experienced it on two different C7s and my truck.

AZRenegade

Thanks for the great personal experience write up. It's Informative, to the point, and helpful.

stingraynick75

See service bulletin P1P5185A, my belt tensioner went out under 10K. It only shuttered when AFM activated.

Chemdawg99

You're welcome and thank you for starting this thread. Very important for the "other side" to be represented, though as has been said, I think people who have had real problems with the AFM are much rarer than an internet forum dedicated to the Corvette would lead you to believe.

Most people buy the Range device simply because they find it incredulous that a V8 should ever drop down to four cylinders for any reason. The perception that AFM damages the car long term is mostly a selling point. Fear is a great motivator.

Tinkertech

GM didn't change the torque tube from aluminum to steel for no reason.
Excessive vibration in caused by V4 mode caused the vibration.
Excessive vibration in M7 cars is why the V4 mode is not used in lower gears.
You can't kill half of the cylinders without inducing excessive vibration.
Excessive vibration destroys things.
Ever wonder why they make shake tables to test items for durability ?

jwmgr8

As with many issues lots of opinions. All worthwhile and helpful.
As an old person who use to like working on his cars the technology has passed me by. My issues with AFM are simple:
1. As stated before I did not by an 8cyl vette to run in 4cyl, or worry about a few mpg?
2. The AFM system is very complex, and adds lots of stuff which will malfunction at some point. Did you know there is a set of exhuast valves near the rear axel that are part of the AFM? Most Corvette owners will not see problem because they will not drive the Corvette very many miles, It is rare to have a 5 year old Vette with more than 30k miles. If we had even half the Vettes sold driven 20k miles per year we might have enough information to determine what works.
3. I do not like buying something to turn off the AFM. I'd prefer GM provide an off switch.
4. My opinion is the AFM contributes to some issues with the A8. So far I've owned two C7. The combination of AFM and A8 did not deliver a smooth distribution of power at various speeds. Turning off the AFM has imporved this. Hech I don't understand why we need 8 speeds? 4 or 6 seem plenty. Ford has gone even further- my 2020 Mustang has a 10 speed?
5. I'd like GM to invest the money in HP, drivability, reducing cost.... But I'm a Corvette guy and well I like Corvettes.

I'm likely the odd ball on many issues? So short reason Simple is better than complex.
The Idea and concept of the C8 has been talked about for decades. I expect at some point I will embrace the looks?? but I'm not there yet. Plus I look at the complexity of the C8? wow! not for me.

Chemdawg99

I’m just relaying my personal experience with AFM. It’s a technology that’s been around for over a decade. Of course, this thread is not a debate on the “drawbacks” of AFM, but rather to relay whether one has had no problems related to allowing the AFM to operate as designed.

AZRenegade

He's correct. The intent of this thread is to ignore opinion and focus on personal experience. Unitil now, in spite of all of the opinions to the contrary, the few personal experiences posted by Corvette owners regarding AFM seem to indicate the system performs as advertised.

ChiefBoats

I can agree to that, opinions mean nothing.

joemessman

I have a 2016 Stingray A8 with over 135,000 miles on it and never any issues. But I have had the Range device to prevent the activation since it has had about 38,000 miles on it. Best automatic I have owned.
I also have a 2019 Z06 A8 with over 50 000 miles on it and no issues with active fuel management, but I had had the Range device in it since day one.
But I did have to have the torque converter replaced sometime back under warranty. Has been good ever since.
I drive both cars real hard. I take the Z06 to Chuckwalla Valley raceway once in a while and really punish it!

Red08

The 49 mpg that you are showing is instant fuel economy. I can get more that 49 in instant fuel economy backing off the accelerator and going downhill. You need to show your average fuel economy

AZRenegade

What I take away from this is that you have two Corvettes with a combined 185,000 miles and have had no problems with the AFM lifters, cam, or other associated parts. Also, you had 38,000 miles on your '16 Corvette with no problems prior to installing the Range unit. Thanks. 👍🏻

ChiefBoats

Nice day today, went for a little ride earlier on the back roads around me, about a 1/4 mile down the road, I hear the phart pipe sound of a 4 banger tuner...........I forgot to flip the on/off switch on for the Range, I keep the NPP open all the time, have an x-pipe, it lets me know when it's not on.

AZRenegade

😂😂 Yeah, I guess that is one of the negatives of using AFM. I've heard the V4 sound in my '15 Sierra but rarely in my Vette. Not because it doesn't exist but between the radio and all of the road noises the exhaust note doesn't come close to registering until I'm accelerating. 😂🤜🏻💥🤛🏻

outrunm

I had an off the record conversation with a dealer service advisor when deciding on whether or not to disable AFM. It was pointed out that there are many more Silverado failures than Corvette, which he attributed to the fact most Corvettes being used as weekend cars with not as many miles put on them and being more pampered in general. Since I tend to treat my vehicles more like Tinder dates than princesses, I decided not to chance it and disabled AFM.

jwmgr8

Many responces are too wordy for most but asking simply what your experience has been with AFM if you use it 100% of time seems not specific enough?
My experience was poor when I used AFM 100% of time. When I stoped using it my driving experience was much better.
I drove my 2016 19k miles at 100%AFM before selling. I had the TQ replaced, and the triple flush. The transmission always seemed to struggle(shudder) when transistion from 8 to 4cyl. When transistion from 4cyl to 8 it seemed like the transmission needed to shift gears sometimes.
Currently I've driven my 2017 5k miles since I got it used with 9400miles. Almost all 5k miles has been with AFM turned off. When I did have AFM on 100% of time(about 500miles)the driving experience was exactly like the 2016 which is why I now drive 100% of time with AFM off.

Maybe there are better ways to ask the question.
For those that have driven their corvette equiped with AFM more than 75k miles and the AFM was active 100% of the time did you have any mechanical problems traced back to the AFM? Yes or No? if yes what?

Most corvettes are only driven a few thousand miles so those might need to be excluded from your survey. Also there are many that track their cars so they might need to be excluded.
How bout the guys that only drive in city traffic? or those that drive in the mountains? It is hard to ask a question and get information that might make sense?

If I was a follower of those that respond on the forum I might just accept what folks say and accept what is actually useful to me. I know we get off topic from time to time.

Have fun and Drive safe! Finish out the crazy 2021 year thinking about how great 2022 will be

ChiefBoats

A combination of the '14 and now the '16 with over 75K and the Range AFM Disabler on, I've experienced no issues, cars run fine.