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Posted
9 minutes ago, A Horse With No Name said:

The CTS V is a sublime automobile indeed...

You could have driven everything on the list and not understood what you were driving...which I do not think is the case. You seem to have a reasonably good eye for cars, and I trust your judgement on them.

 

Not understood what I was driving? I don't even know how to answer that.

Posted
3 hours ago, Frisky Dingo said:

 

Not understood what I was driving? I don't even know how to answer that.

That was not an accusation...I was saying that you could have been clueless but we're not. Sorry, thought my post was more clear.

Posted
16 hours ago, Frisky Dingo said:

 

Considering what I do for a living, that's an incredibly daft statement. Which shouldn't surprise me.

Since I have no idea what you do, how is it daft if someone does not know what you do.

Posted
On 4/29/2017 at 9:41 AM, Cmicasa the Great said:

It, as per my experience, depends on how one drives these vehicles from the git. I bet good money that U can take my Aline "14 Impala" and drive her after U've just driven another '14 with similar miles on the ODO and believe that U are shifting two totally different cars. That GM transmissions LEARN your driving style is not a myth in my opinion. There is no way a driver in one of them for an hour or a day can claim that the tranny is one way or another over the long run. The only real tune(out) needed in some GM trannies is the 1-4 (CAGS) program in manuals for enthusiastic driving. 

You're talking to someone with experience tuning GM transmissions (including the 6T70 used by the 2014 Impala), what you said is incorrect.

While the transmissions do have a "learning algorithm," it does not affect shift points. It's really pretty underwhelming when you understand it, but it mostly affects shift feel.

The transmission shifts based on predetermined tables of throttle versus speed, written by engineers overseen by beancounters. They are not subject to change. Some GM performance automatics will temporarily switch to a more aggressive dormant shift table when driven hard, but that's the extent of it.

If a stock CTS-V driving 60 mph will downshift from 8th gear to 6th with 20% throttle, it will do the same thing after 5 different owners and 150,000 miles.

  • Agree 2
Posted
On 4/30/2017 at 11:25 PM, cp-the-nerd said:

You're talking to someone with experience tuning GM transmissions (including the 6T70 used by the 2014 Impala), what you said is incorrect.

While the transmissions do have a "learning algorithm," it does not affect shift points. It's really pretty underwhelming when you understand it, but it mostly affects shift feel.

The transmission shifts based on predetermined tables of throttle versus speed, written by engineers overseen by beancounters. They are not subject to change. Some GM performance automatics will temporarily switch to a more aggressive dormant shift table when driven hard, but that's the extent of it.

If a stock CTS-V driving 60 mph will downshift from 8th gear to 6th with 20% throttle, it will do the same thing after 5 different owners and 150,000 miles.

Well.. maybe I just drive too damn AGGRESSIVE.. all the time.. in all the cars I drive, which these days.. thankfully are all GM i70mfl.jpg

  • Agree 1
Posted
On 4/30/2017 at 11:25 PM, cp-the-nerd said:

You're talking to someone with experience tuning GM transmissions (including the 6T70 used by the 2014 Impala), what you said is incorrect.

While the transmissions do have a "learning algorithm," it does not affect shift points. It's really pretty underwhelming when you understand it, but it mostly affects shift feel.

The transmission shifts based on predetermined tables of throttle versus speed, written by engineers overseen by beancounters. They are not subject to change. Some GM performance automatics will temporarily switch to a more aggressive dormant shift table when driven hard, but that's the extent of it.

If a stock CTS-V driving 60 mph will downshift from 8th gear to 6th with 20% throttle, it will do the same thing after 5 different owners and 150,000 miles.

Honest question:

The 5-speed auto in my '04 CTS did seem to adjust to my driving pattern when it was in sport mode.  If I put it in sport and drove normally, it would hold a gear a bit longer before shifting, but otherwise drove normally. If I was in sport mode and being very aggressive, it would hold a lower gear longer even after I let off the gas..... if I calmed down, then it would go back to normal sport mode.... but it always took a few minutes of driving before it did.  I realize that it is not the memory that @Cmicasa the Great was talking about, but the transmission did seem to adjust to variations in driving more distinctly.   I will say that I have yet to experience a transmission with that level of variation in attitude since then because just after that model, everyone went to paddle shifters and the sport-automatic modes don't seem to be as aggressive. Did I imagine it?

Posted
46 minutes ago, Drew Dowdell said:

Honest question:

The 5-speed auto in my '04 CTS did seem to adjust to my driving pattern when it was in sport mode.  If I put it in sport and drove normally, it would hold a gear a bit longer before shifting, but otherwise drove normally. If I was in sport mode and being very aggressive, it would hold a lower gear longer even after I let off the gas..... if I calmed down, then it would go back to normal sport mode.... but it always took a few minutes of driving before it did.  I realize that it is not the memory that @Cmicasa the Great was talking about, but the transmission did seem to adjust to variations in driving more distinctly.   I will say that I have yet to experience a transmission with that level of variation in attitude since then because just after that model, everyone went to paddle shifters and the sport-automatic modes don't seem to be as aggressive. Did I imagine it?

I do not think you did as I also have noticed the change since the first CTS.

Posted
1 hour ago, Drew Dowdell said:

Honest question:

The 5-speed auto in my '04 CTS did seem to adjust to my driving pattern when it was in sport mode.  If I put it in sport and drove normally, it would hold a gear a bit longer before shifting, but otherwise drove normally. If I was in sport mode and being very aggressive, it would hold a lower gear longer even after I let off the gas..... if I calmed down, then it would go back to normal sport mode.... but it always took a few minutes of driving before it did.  I realize that it is not the memory that @Cmicasa the Great was talking about, but the transmission did seem to adjust to variations in driving more distinctly.   I will say that I have yet to experience a transmission with that level of variation in attitude since then because just after that model, everyone went to paddle shifters and the sport-automatic modes don't seem to be as aggressive. Did I imagine it?

Cadillac automatics have additional responses to driver input. For example, many GM performance cars in sport mode automatically downshift when the computer senses steering input going through a sweeping turn. Like I said in my other post, aggressive driving can trigger different things as well.

I don't know all the ins and outs of GM performance progamming, so I can't give a complete answer. I just know that the shift tables and responses to input are written in stone unless a tune is applied.

To give a brief idea of what's in the TCM, all GM 6-speeds I've looked at had 3 separate automatic shift tables not counting the paddle shifters or limp mode. One of them is standard driving mode, one is for cruise control, and the third is sport mode (and possibly tow/haul mode for trucks). In my Malibu, sport mode was permanently dormant.

Posted
7 hours ago, cp-the-nerd said:

Cadillac automatics have additional responses to driver input. For example, many GM performance cars in sport mode automatically downshift when the computer senses steering input going through a sweeping turn. Like I said in my other post, aggressive driving can trigger different things as well.

I don't know all the ins and outs of GM performance progamming, so I can't give a complete answer. I just know that the shift tables and responses to input are written in stone unless a tune is applied.

To give a brief idea of what's in the TCM, all GM 6-speeds I've looked at had 3 separate automatic shift tables not counting the paddle shifters or limp mode. One of them is standard driving mode, one is for cruise control, and the third is sport mode (and possibly tow/haul mode for trucks). In my Malibu, sport mode was permanently dormant.

Interesting, so to flash a transmission in the Malibu, all one would have to do is wake up sport mode?

Posted
8 hours ago, cp-the-nerd said:

Cadillac automatics have additional responses to driver input. For example, many GM performance cars in sport mode automatically downshift when the computer senses steering input going through a sweeping turn. Like I said in my other post, aggressive driving can trigger different things as well.

I don't know all the ins and outs of GM performance progamming, so I can't give a complete answer. I just know that the shift tables and responses to input are written in stone unless a tune is applied.

To give a brief idea of what's in the TCM, all GM 6-speeds I've looked at had 3 separate automatic shift tables not counting the paddle shifters or limp mode. One of them is standard driving mode, one is for cruise control, and the third is sport mode (and possibly tow/haul mode for trucks). In my Malibu, sport mode was permanently dormant.

Cool to know. Like I said, the sport mode in that 5-speed was extra aggressive when pushed hard, sport mode in more recent transmissions don't have such a drastic difference in mode... Even the Cadillacs.

  • Agree 1
Posted
2 hours ago, A Horse With No Name said:

Interesting, so to flash a transmission in the Malibu, all one would have to do is wake up sport mode?

No. All three shift tables in the Malibu were garbage and I rewrote standard and cruise control from scratch. I attempted to assign the sport mode to something so I could have regular, cruise, and sport depending on my input, but I gave up after a half dozen failed attempts.

After that failed, I created a compromised regular/sport mode, the car drove like a dream on that shift pattern so I had no complaints other than I wanted a stick shift.

1 hour ago, Drew Dowdell said:

Cool to know. Like I said, the sport mode in that 5-speed was extra aggressive when pushed hard, sport mode in more recent transmissions don't have such a drastic difference in mode... Even the Cadillacs.

I tried finding a gen 1 CTS stock tune to show you screen shots, but apparently the 5-speed automatic isn't supported by HPTuners, so the TCM appears blank.

  • Agree 2
Posted

Interesting...Would love to flash a car like that.  I was going to get a tune for the DSG in my 2015 TDI Jetta but ended up selling ti back to VW several weeks ago.

Posted
10 minutes ago, cp-the-nerd said:

I tried finding a gen 1 CTS stock tune to show you screen shots, but apparently the 5-speed automatic isn't supported by HPTuners, so the TCM appears blank.

It's fine. I'm not sure I'd even know what I was looking at anyway. 

  • Agree 1
Posted
Just now, Drew Dowdell said:

It's fine. I'm not sure I'd even know what I was looking at anyway. 

...so what are you and Albert looking at as your next vehicle? Sounds like you might not mind a performance vehicle of sorts.

Posted
Just now, A Horse With No Name said:

...so what are you and Albert looking at as your next vehicle? Sounds like you might not mind a performance vehicle of sorts.

Well, that's going to be a ways off I think. I'm stuck where I am for now due to job uncertainties.  I still want an Avalanche or Escalade EXT though there may be business reasons to lease a truck for me......For him, probably move him to a Jeep GC or Durango once we have some stability... I just won't mention the Hemi under the hood when I pick one out. 

  • Agree 1
Posted
38 minutes ago, Drew Dowdell said:

Well, that's going to be a ways off I think. I'm stuck where I am for now due to job uncertainties.  I still want an Avalanche or Escalade EXT though there may be business reasons to lease a truck for me......For him, probably move him to a Jeep GC or Durango once we have some stability... I just won't mention the Hemi under the hood when I pick one out. 

I am not real happy with you (or un-happy for that matter!).  You and 2QuickZ's suggested trying the Hemi/auto combo...After driving a V8 300 I think really bad (but really good!) things every time I pass a Challenger, Charger, or V8 300 on the highway.

Posted (edited)
12 hours ago, cp-the-nerd said:

Cadillac automatics have additional responses to driver input. For example, many GM performance cars in sport mode automatically downshift when the computer senses steering input going through a sweeping turn. Like I said in my other post, aggressive driving can trigger different things as well.
 

In the case of a 2007 SRX V8 in Sport Mode, I seem to invoke Performance Algorithm Shifting quite frequently while merging on highways.  The triggers are likely accelerator pedal movement characteristics and accelerometer data.  Once PAS mode is engaged, it won't upshift even when the accelerator is released; this enables a quicker response when the driver gets back on the throttle to navigate around slower traffic or pull out of a sharp corner. 

Edited by KevinW
Rephrasing for clarity
  • Agree 2
Posted
5 minutes ago, KevinW said:

In Sport Mode, I seem to invoke Performance Algorithm Shifting quite frequently while merging on highways, in the case of a 2007 SRX V8.  The triggers are likely accelerator pedal movement characteristics and accelerometer data.  Once PAS mode is engaged, it won't upshift even when the accelerator is released; this enables a quicker response when the driver gets back on the throttle to navigate around slower traffic or pull out of a sharp corner. 

I believe that's the case, but I haven't been able to find the parameters responsible for that in the tune. I'm sure it's there, but there are so many data points to sort through, it's like opening a 400 page novel and searching for one particular paragraph.

Posted
43 minutes ago, KevinW said:

In the case of a 2007 SRX V8 in Sport Mode, I seem to invoke Performance Algorithm Shifting quite frequently while merging on highways.  The triggers are likely accelerator pedal movement characteristics and accelerometer data.  Once PAS mode is engaged, it won't upshift even when the accelerator is released; this enables a quicker response when the driver gets back on the throttle to navigate around slower traffic or pull out of a sharp corner. 

Yes, that's what I'm describing from my 2004.  The more recent automatics don't seem to hold that shift like this particular one does. 

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