2022 silverado 2500hd 6.6l gas excessive cranking to start

[Dan Lawson]

I have a 22 LT 6.6l gas with 2500 miles took it to the dealership because it seems to excessively crank in the morning 3-4 seconds until start otherwise fires right off during the day,tested battery at my house showed low voltage dealership had it 2 days couldn't say it was the module keeping bcm awake but blamed my dash camera I've keep it unplugged so not to drain battery and back from the dealership still excessively cranks,I'm thinking bad battery but am going to take it to another dealership since I have lost faith and the actual diagnostic test they did at the dealership I brought it to first,just seeing if anyone else has had an issue of battery drain overnight or excessive cranking 

[Another JR]

When you first open the door do you hear the fuel pump run to pre-pressurize the fuel system?

[Dan Lawson]

14 hours ago, Another JR said:

When you first open the door do you hear the fuel pump run to pre-pressurize the fuel system?

Yes

[Crazy Canuck]

Did they or you load test the battery?  May be a good check.

[Dan Lawson]

1 hour ago, Crazy Canuck said:

Did they or you load test the battery?  May be a good check.

I have no idea,they never gave me paperwork,I truly believe the battery is bad,I'm going to schedule it at another dealership after I test it at our shop. 

I gave this smaller chevy dealership a try but was very unsatisfied with the attempt or care they showed 

[2020_3500HD]

If the outside temp is cold (can’t remember the exact cut off) the gm di motors will have an extended crank time.  I experienced this on my previous truck 2015 half ton and my 2020 6.6 truck does the same.  Has to do with making sure proper fuel pressure is built up before firing the injectors.  Hope this helps.

[Dan Lawson]

17 hours ago, 2020_3500HD said:

If the outside temp is cold (can’t remember the exact cut off) the gm di motors will have an extended crank time.  I experienced this on my previous truck 2015 half ton and my 2020 6.6 truck does the same.  Has to do with making sure proper fuel pressure is built up before firing the injectors.  Hope this helps.

Well thats when it does it the most under 40 degrees 

[Another JR]

17 hours ago, 2020_3500HD said:

If the outside temp is cold (can’t remember the exact cut off) the gm di motors will have an extended crank time.  I experienced this on my previous truck 2015 half ton and my 2020 6.6 truck does the same.  Has to do with making sure proper fuel pressure is built up before firing the injectors.  Hope this helps.

I did not experience extended cranking during a recent cold stretch here in the mid 20s F (that counts as very cold here in the Seattle area).  So the threshold must be lower than that. 

[2020_3500HD]

I found and attached the tsb from when I had my 2015 truck.  It has a chart showing approx crank times associated with different temps.

[GP9]

On 3/2/2022 at 3:38 AM, 2020_3500HD said:

If the outside temp is cold (can’t remember the exact cut off) the gm di motors will have an extended crank time.  I experienced this on my previous truck 2015 half ton and my 2020 6.6 truck does the same.  Has to do with making sure proper fuel pressure is built up before firing the injectors.  Hope this helps.

I’ve got a 2022 3500 and it does the same thing. The crank is slightly extended for a cold start in low temps. It seems to cold start with normal cranking when the weather is warm.

[Jettech1]

We actually had 10' weather here in Atlanta during this past Christmas.  Truck started almost instantly.  Never a long cranking at all...Not a difference between 95' and 10'.  That definitely points towards a bad battery with a bad cell in it.  Sometimes load testers are not spot on.  You need the volts to push out the amps.  Those load testers don't always tell the whole truth.  A new battery will probably solve all your problems.