2024 Tahoe - 10L80 issue

[acesttz]

I searched the forum before posting this and did not find anything.

2024 Tahoe HC 6.2L - 30,000 miles

the truck has a small but noticeable vibration between 30 - 33 mph and between 50-52 mph. The vibration only occurs at light throttle, but as soon as throttle is increased, it goes away. It feels like a torque converter issue, but without the ability to see the lockup percentage I cannot tell for sure. Also, the vibration is more noticeable in the passenger seat that the driver’s.

And the dealer has no idea what is causing the vibration.

Anyone have any ideas what is causing this or anyone have a similar experience?

 

[pa31p]

On my 2023 5.3 I had similair issue. (DFM) can you try running it in manual shift mode and run up to 8th gear only see if it still does it. in 8th DFM is disabled. on mine it was cylinder deactivation. almost felt like driving over rumble strips.

There’s an aftermarket solution now if that’s it.

 

[acesttz]

Thank you. I did not think about the DFM being the issue.

Have you used the aftermarket solution?

 

[StephenPT]

When you give it throttle, the engine goes back to V8 (DFM is now off). Since your rumble goes away when this happens I’d confidently say it’s a DFM vibration.

https://www.rangetechnology.com/products/afm-dfm_disabler/parts/RA007

 

[acesttz]

I ordered the Range disabler. After install I will report back.

 

[fondupot]

I ordered the Range disabler. After install I will report back.

I have it on my 2021 5.3. I like it.

 

[acesttz]

The Range Disabler fixed the vibration.

 

[Marky Dissod]

The Range disabler fixed the vibration.

This almost certainly means that it's a cylinder deactivation issue that goes away once it's a real V8 again.

Just checking: did you temporarily uninstall the Range plug-in, to see if the vibes came back?

 

[fondupot]

This almost certainly means that it's a cylinder deactivation issue that goes away once it's a real V8 again.

Just checking: did you temporarily uninstall the Range plug-in, to see if the vibes came back?

No need. My 2021 did the same as OP described. And after the Range module it’s smooth as can be. DFM is such garbage the engines run so much better without it.

 

[Marky Dissod]

DFM is such garbage the engines run so much better without it.

In principle / theory, DFM cylinder valve deactivation is a better idea than AFM.
In practice, the parts are simply not robust enough to withstand real world variables,
especially when compared to always-V8 lifters and such.
GM restarted cylinder valve deactivation AGAIN in 2004.
After 20 years, they STILL haven't bothered to improve the pertinent hardware?
I think GM is deliberately trying to make their engines die (or suck HARD) before 200,000 miles.