Oncoming volume preset, max and min volume, why differences between years in 6l80s?

[old4door]

So I'm trying to gain more knowledge with tuning 6l80s and have made on observation that doesn't make much sense to me. I've got a 2009 G8 and a 2015 Sierra, both with a 6l80. Internally they should be pretty much the exact same, I know there have been a couple part updates/upgrades but clutch packs and such are exactly the same. So why are the oncoming volume presets so drastically different.

G8 Sierra
1-2 = 60 24
2-3 = 21.5 24
3-4 = 30 29
4-5 = 18 24
5-6 = 50 25

There are min volumes on the Sierra while the G8 is just zeroed out. Can anyone give me an idiots guide explanation on why this is or how it makes sense. I searched a number of different ways but no one has brought this up before from what I can see.

Thanks in advance for sharing!

[5FDP]

My guess is because it's two different kinds of vehicles and two different types of controllers.

Lighter car vs heavy truck and earlier E38 controller compared to a E92 controller.

A lot less is different between a 2012 truck and a 2016 truck for example but some of those tables mentioned are still different. And those transmissions are nearly the same

[old4door]

My guess is because it's two different kinds of vehicles and two different types of controllers.

Lighter car vs heavy truck and earlier E38 controller compared to a E92 controller.

A lot less is different between a 2012 truck and a 2016 truck for example but some of those tables mentioned are still different. And those transmissions are nearly the same

This makes me think the values have very little effect on the way it shifts. But people say adjusting the oncoming preset volume should be done when using additional clutches, etc. Seems to me adjusting oncoming and offgoing adaptives are more critical for getting shifts working well.