Hey Tex I have read several posts by you and you seem to have a good knowledge base for the computer tuning of these trucks and if you don’t mind I would like to pick your brain a little.

Here goes,
As we all have taken as rule of thumb the shift on the fly tuners are not a good product for us and I understand the reasons.... Not properly tuning tranny and so forth. I do understand how programming works within computers and how logic works for computers so I got the SCT X-3 and have been very happy with the tunes that ID provided me.

However,,,, It has come to my attention that out transmission control module has some "adaptive" intelligence and can raise or lower shift points as needed or being commanded by our right foot.
Example..... I have been running a very mild street tune and having a little fun with it Now.... I hooked on to my boat (5-6k) and hit the highway. The first several miles the truck shifted like I was rodding around town unloaded and down shifted the same. Every hill I came on it down shifted and was "ready" for some throttle. After several miles of this I started to notice my shifting points changing. The truck would NOT downshift on the little mole hills and push through just fine. (as I would expect) It began to shift more "normal" to what I have come to expect from a 9k truck pulling a boat.

So..... I guess by seeing this I have related it to the "adaptive Intelligence" of the transmission. Does this seem logical to you based on the knowledge you have with our trucks internal programming?

More-over If the TCM does change shift points based on driving habbits then what good is truly programing it? Does it only change within programing limits?

I'm sorry if this is a little hard to follow... I am trying to explain it the best I can.

Thanks for any input you may have.... This has gotten me thinking WAY to hard
As you cna probably tell I have to know how things tick... Mind of an engineer I guess.

Cheers

 

Yes, there are adaptative constraints within a given program. Which is one of the main reasons why most people tell you to vary your driving in order for the TCM not to become in a habit of one type of driving situation. Your mild street tunes aren't all that far from a tow tune which is probably why it handled more along the lines that you would believe it should handle when towing.

Take for instance Matt's "hybrid race" tune. 1/2 throttle or less and it runs like an economy tune; mesh it down and be prepared to hold on. Pretty much the same thing you are mentioning, behavior within a set of parameters.

People also mention that awhile awhile the tranny shifting would get "soft" and not be as "crisp" as it once was(another reason for trying to keep it "guessing" with variable driving habits. However, most of the time a simple "reprogram" of the tune that you are running will help firm up those shifts like they once were.

As to what good it is for programming the TCM, it is to set those limits for the TCM to operate under. If you are running a tune that requires aggressive behavior(crisp, firm, aggressive shifts) you don't want it to adapt to a pretty soft shifting as that would not be good for the intermediate clutch. Programming is more about setting boundaries if you will.

 

Got'ca

As I said I am familure with computer logic as i write code for building automation systems but these programs are a blank sheet and do nothing but what i tell them to.
It seemed logical what I was thinking but I realy have no one on a local level that would be able to answer this question. The tech I use is great with grease up to his elbows but it's all smoke and mirrors when it comes to computers.

Your responce clears it up perfectly!

Thank you!