Auto Start/Stop Feature

lryfer · April 4

So I am looking at buying a new 2022 GMC Sierra 1500 Limited. On the build sheet it has -50 for Start/Stop feature. Why is this? Are there issues with this feature as I have heard of many GM issues with engines, transmissions etc?

Any issues with the 2022 Sierra Limited to be concerned about?

Thanks for input.

CamGTP · April 4

Chip shortage. That is the only reason.

lryfer · April 4

So with the chip shortage can the truck get he start stop installed with a chip in the future if one wanted to do so? Doesnt that mess up the engine the start stop feature? Just curious.

HellRazor · April 10

The Start/Stop feature doesn't mess up the engine per se. But the starter in every vehicle only has so many starts in its lifetime.
When you drive to the store, for example, you'll start your vehicle maybe 2 times.
If you have the Start/Stop feature activated, your vehicle may shut down and start back up at every stop sign and red light on your way to and from wherever you're going. This constant restarting of your vehicle uses up the available starts your starter has in it's lifetime thus reducing your starters life.

The feature that supposedly messes up the engine is the Dynamic Fuel Management (DFM). That has been linked to the seized lifters and bent pushrods many V8 Silverado/GMC owners are having. The problem is when some of the cylinders are deactivated during DFM they aren't getting lubricated. So when these cylinders get activated again, after not getting lubricated, they seize up and fail.

As far as I'm concerned, they can take both DFM AND Start/Stop features and stick them in the trash bin of stupid ideas.

Edited April 10 by HellRazor

redwngr · April 22

Fwiw, the starter used on a stop/start truck is not the same one as used on the non stop/start engines.

I have no idea if they still use the stop/start starter on the trucks that don't have the chip/module to operate it.

There is a long explanaton of the difference in the upfitter docs.

lryfer · May 29

On 4/10/2022 at 2:27 PM, HellRazor said:

The Start/Stop feature doesn't mess up the engine per se. But the starter in every vehicle only has so many starts in its lifetime.
When you drive to the store, for example, you'll start your vehicle maybe 2 times.
If you have the Start/Stop feature activated, your vehicle may shut down and start back up at every stop sign and red light on your way to and from wherever you're going. This constant restarting of your vehicle uses up the available starts your starter has in it's lifetime thus reducing your starters life.

The feature that supposedly messes up the engine is the Dynamic Fuel Management (DFM). That has been linked to the seized lifters and bent pushrods many V8 Silverado/GMC owners are having. The problem is when some of the cylinders are deactivated during DFM they aren't getting lubricated. So when these cylinders get activated again, after not getting lubricated, they seize up and fail.

As far as I'm concerned, they can take both DFM AND Start/Stop features and stick them in the trash bin of stupid ideas.

So can you turn off the DFM and run just like the straight 8 per say or stuck with it? I just bought a 2022 Sierra 1500 limited with the DFM installed. Picking up saturday

energyman2005 · June 2

My new AT4 has the auto stop/start feature. In three weeks of owning the truck, it is turned off maybe 4 times in total at stoplights. So it doesn't even work as intended...

Dirk13 · June 2

1 hour ago, energyman2005 said:

My new AT4 has the auto stop/start feature. In three weeks of owning the truck, it is turned off maybe 4 times in total at stoplights. So it doesn't even work as intended...

It is not intended to go into auto stop at every single stop. There are many different criteria that the truck uses to determine whether or not it can turn itself off.

Trucks not warmed up? Won’t shut off. Blasting ac? Won’t shut off.
Something using a high amount of power? Won’t shut off.

and so on

Acpantera · June 9

On 4/22/2022 at 11:16 AM, redwngr said:

Fwiw, the starter used on a stop/start truck is not the same one as used on the non stop/start engines.

I have no idea if they still use the stop/start starter on the trucks that don't have the chip/module to operate it.

There is a long explanaton of the difference in the upfitter docs.

The Battery is also upgraded to an AGM in the auto stop/start featured vehicles, well worth 50 bucks

energyman2005 · June 10

On 6/2/2022 at 6:47 PM, Dirk13 said:

It is not intended to go into auto stop at every single stop. There are many different criteria that the truck uses to determine whether or not it can turn itself off.

Trucks not warmed up? Won’t shut off. Blasting ac? Won’t shut off.
Something using a high amount of power? Won’t shut off.

and so on

Good to know!!