How to tell if AFM is active?

[Myjigglybelly]

How can I tell if AFM is active? In the previous gen Tahoe/Yukon, I was able to see V8 icon change to V4 in the instrument cluster.

 

[DocDoug]

I also updated to a 2022 Tahoe and can’t find the V8 to V4 indicator. I gave up looking and accepted the fact that GM wants consumers to forget about this feature, as it only draws attention to potential problems and furthers the discussion. Having said that, I get great highway mileage with my 2022 5.3. See photo.

 

[B-train]

I think you'll have to train your senses to the slight audible noises to be able to tell. They have done a good job at hiding it though

 

[Myjigglybelly]

I also updated to a 2022 Tahoe and can’t find the V8 to V4 indicator. I gave up looking and accepted the fact that GM wants consumers to forget about this feature, as it only draws attention to potential problems and furthers the discussion. Having said that, I get great highway mileage with my 2022 5.3. See photo.

Wow I also have a 5.3 on my 2023 Yukon slt. How do you get such good mileage on the hwy? I think the best I have gotten is around 24mpg driving around 60mph. I generally drive very mild (no harsh acceleration and lots of coasting).

 

[Toasty]

How can I tell if AFM is active? In the previous gen Tahoe/Yukon, I was able to see V8 icon change to V4 in the instrument cluster.

You won't, at least not without extra hardware/gauges. (Something like the Banks iDash may show this via OBDII data) - the new DFM system can vary in how many cylinders are deactivated, rather than just shutting off 4.

 

[swathdiver]

You guys don't have AFM with half the motor shutting down, you have DFM where every cylinder has the ability to be turned off. So you could be cruising on 2 or 5 or 7 cylinders depending on conditions.

This applies to the 5.3 L84 and 6.2 L87 engines.

https://gmauthority.com/blog/gm/general-motors-technology/general-motors-propulsion-technology/general-motors-dynamic-fuel-management-cylinder-deactivation-technology/

 

[dancastro]

Wow I also have a 5.3 on my 2023 Yukon slt. How do you get such good mileage on the hwy? I think the best I have gotten is around 24mpg driving around 60mph. I generally drive very mild (no harsh acceleration and lots of coasting).

Same here....how are you getting 29? removing extra seats, spare, etc?

 

[GMCnewbee]

I have never been able to notice any change when driving. We have a 2022 Denali and it just seems to run real smooth at all times.

 

[Baja_Bob]

I had a 2016 Silverado with the 5.3 and you would notice a change in exhaust sound when going from v8 to v4, on the highway the exhaust would have make more of a drone noise when in v4 mode, I do miss the v8-v4 indicator on my Yukon.

 

[A10MileHusker]

Same here....how are you getting 29? removing extra seats, spare, etc?

Going downhill.

 

[Saltydog]

Wow I also have a 5.3 on my 2023 Yukon slt. How do you get such good mileage on the hwy? I think the best I have gotten is around 24mpg driving around 60mph. I generally drive very mild (no harsh acceleration and lots of coasting).

I have seen about 29 MPG with 21 Yukon 5.3, normal Highway is about 24-26mpg.

 

[Saltydog]

I have enough seat time in our Yukon and I can tell by the throttle response and the engine/exhaust sound when DFM is active.

That said, GM did a very good job of masking the sound of it.

 

[Doubeleive]

How can I tell if AFM is active? In the previous gen Tahoe/Yukon, I was able to see V8 icon change to V4 in the instrument cluster.

you should be able to feel it and hear it, it drives me absolutely insane.

 

[B520044]

you should be able to feel it and hear it, it drives me absolutely insane.

Drives me crazy too. I feel it more than anything. To me its like driving a manual transmission in the highest gear when going 40mph.

 

[greg_tahoe84]

Is the newer DFM any better?

 

[Doubeleive]

Is the newer DFM any better?

it's just a jig to keep the epa happy, doesn't help the consumer in any manner

 

[vcode]

Same here....how are you getting 29? removing extra seats, spare, etc?

Note his best and average mpg's are the same. Doesn't compute.