Adjustable Transmission Modulators
#22
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top notch stuff.
anyways, a burner, some flash PROMs and assuming you have some kind of decent soldering ability, a HDR1 and that'* all you'll need to program your specific car. to modify the tune (for the shift points or other stuff...), you'll need tunerpro and the proper defintion for your car. tunerpro is free (tunerpro RT will display a nag screen for 10 seconds every time you launch the program unless you donate to the author), definitions are also free(the community generates them). some defs are more complete than others, but most of the 3800 stuff is pretty well defined.
then to track your progress, an ALDL cable would be a good investment. can either make your own or buy one premade.
#23
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Believe it or not, I follow the basic jist of what was said above.. But it'* not very likely I'll be attempting any of that any time soon lol.. I also understand the basic jist of how a nuclear reactor works, but it'* not very likely I'll be attempting to build one of those any time soon either lol..
And not just because I can't solder anything electrical to save my life (though I can sweat pipes pretty damn well). Thanks for the info above, though..
As for the Adjustable Transmission Modulator, it is in (I installed it while doing the left front motor mount). One and a half turns in seems pretty good on my LeSabre, 2 turns and above seems like it'd stress the crap-*** motor mounts too much over time, not to mention the driveline components.. The engagement of OD even feels like a firm shift when the modulator setting is too high lol..
I still intend to come up with a simple way to manually control, when desired/needed, the engagement of the lock-up converter, and possibly, the OD, via a switch on the dash. It will be illuminated (or have an indicator light) for less likelihood of forgetting to disengage the lock-out of the lock-up..
Too damn many long grades to pull around here: You're either lugging the hell out of the engine or blasting up the grades in a constant state of acceleration to prevent the lock-up from engaging.
Neither is satisfactory
And not just because I can't solder anything electrical to save my life (though I can sweat pipes pretty damn well). Thanks for the info above, though..
As for the Adjustable Transmission Modulator, it is in (I installed it while doing the left front motor mount). One and a half turns in seems pretty good on my LeSabre, 2 turns and above seems like it'd stress the crap-*** motor mounts too much over time, not to mention the driveline components.. The engagement of OD even feels like a firm shift when the modulator setting is too high lol..
I still intend to come up with a simple way to manually control, when desired/needed, the engagement of the lock-up converter, and possibly, the OD, via a switch on the dash. It will be illuminated (or have an indicator light) for less likelihood of forgetting to disengage the lock-out of the lock-up..
Too damn many long grades to pull around here: You're either lugging the hell out of the engine or blasting up the grades in a constant state of acceleration to prevent the lock-up from engaging.
Neither is satisfactory
#24
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not that i recommend it, but the 4T60E does have an acceptable electrical scheme to force 4th gear off and to force TCC on/off via rocker switches.
however, the easier thing to do would be to just drop the shifter into D instead of OD. instant downshift since the manual valve overrides the shift solenoids, even if the PCM were commanding 4th gear (it shouldn't when the shifter moves though, it tracks it).
keep in mind if you force the TCC off when the PCM expects it to be on, it will possibly disable TCC until you do a key cycle due to the PCM tracking TCC slip (pretty sure the 3800s started doing this when they got the 4T60E). DTCs are possible as well.
hence my recommendation of making your own settings via reprogamming. i honestly don't know how i got along without mine.
however, the easier thing to do would be to just drop the shifter into D instead of OD. instant downshift since the manual valve overrides the shift solenoids, even if the PCM were commanding 4th gear (it shouldn't when the shifter moves though, it tracks it).
keep in mind if you force the TCC off when the PCM expects it to be on, it will possibly disable TCC until you do a key cycle due to the PCM tracking TCC slip (pretty sure the 3800s started doing this when they got the 4T60E). DTCs are possible as well.
hence my recommendation of making your own settings via reprogamming. i honestly don't know how i got along without mine.
#25
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Yeah, it sounds like we would be going through an awful lot of trouble to accomplish the same thing I can by pulling the shifter out of overdrive.
#26
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not that i recommend it, but the 4T60E does have an acceptable electrical scheme to force 4th gear off and to force TCC on/off via rocker switches.
however, the easier thing to do would be to just drop the shifter into D instead of OD. instant downshift since the manual valve overrides the shift solenoids, even if the PCM were commanding 4th gear (it shouldn't when the shifter moves though, it tracks it).
however, the easier thing to do would be to just drop the shifter into D instead of OD. instant downshift since the manual valve overrides the shift solenoids, even if the PCM were commanding 4th gear (it shouldn't when the shifter moves though, it tracks it).
I've entertained the thought of putting in a TCC override switch, wired to the switch above the brake pedal, but honestly, I couldn't think of a real need for it.
#28
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Plenty of replies about 4th Gear (which is actually OD).
But 4th Gear/OD isn't the real issue lol..
Yep, I can just slide the shifter from OD to D if needed, so no real need for a separate switch there.
The biggest issue, for me, especially in our hilly terrain, is the TCC, and the way the torque converter locks up on grades, dragging down the rpm & roadspeed and lugging the engine at common speeds well below the point where OD kicks in.
I agree - reprogramming the trans would be the best option. I have neither the tools nor equipment nor ability to do that. Nor do I know anyone around here who does.
That'* a big part of the reason for the idea of an override switch for the TCC.
I found these 2 points of particular interest -
Originally Posted by RobertISaar
"not that i recommend it, but the 4T60E does have an acceptable electrical scheme to force 4th gear off and to force TCC on/off via rocker switches."
Cool. But why is it not recommended, and just what is that scheme
(IE: Simply put a switch on the wire that leads from the PCM to the TCC?)
Originally Posted by RobertISaar
"keep in mind if you force the TCC off when the PCM expects it to be on, it will possibly disable TCC until you do a key cycle due to the PCM tracking TCC slip (pretty sure the 3800s started doing this when they got the 4T60E). DTCs are possible as well."
So if I'm following you, there is an acceptable electrical scheme to force TCC on/off via rocker switches, but it'* not recommended only because of the possibility of a DTC.. Correct? Or is there another reason it'* not recommended, such as the possibility of transmission damage?
And is the acceptable electrical scheme to simply put a switch on the wire that leads from the PCM to the TCC?
If not, what is the scheme?
If so, where would I find that wire, just to try a test..?
Is it possible for OD to engage while the TTC is disabled? Would it damage the transmission? Could it result in an explosion, violent enough to launch bits & pieces of the car into the lower stratosphere and leaving a huge smoking crater in the ground..? If so, I'll keep the selector in Drive during the test.
But 4th Gear/OD isn't the real issue lol..
Yep, I can just slide the shifter from OD to D if needed, so no real need for a separate switch there.
The biggest issue, for me, especially in our hilly terrain, is the TCC, and the way the torque converter locks up on grades, dragging down the rpm & roadspeed and lugging the engine at common speeds well below the point where OD kicks in.
I agree - reprogramming the trans would be the best option. I have neither the tools nor equipment nor ability to do that. Nor do I know anyone around here who does.
That'* a big part of the reason for the idea of an override switch for the TCC.
I found these 2 points of particular interest -
Originally Posted by RobertISaar
"not that i recommend it, but the 4T60E does have an acceptable electrical scheme to force 4th gear off and to force TCC on/off via rocker switches."
Cool. But why is it not recommended, and just what is that scheme
(IE: Simply put a switch on the wire that leads from the PCM to the TCC?)
Originally Posted by RobertISaar
"keep in mind if you force the TCC off when the PCM expects it to be on, it will possibly disable TCC until you do a key cycle due to the PCM tracking TCC slip (pretty sure the 3800s started doing this when they got the 4T60E). DTCs are possible as well."
So if I'm following you, there is an acceptable electrical scheme to force TCC on/off via rocker switches, but it'* not recommended only because of the possibility of a DTC.. Correct? Or is there another reason it'* not recommended, such as the possibility of transmission damage?
And is the acceptable electrical scheme to simply put a switch on the wire that leads from the PCM to the TCC?
If not, what is the scheme?
If so, where would I find that wire, just to try a test..?
Is it possible for OD to engage while the TTC is disabled? Would it damage the transmission? Could it result in an explosion, violent enough to launch bits & pieces of the car into the lower stratosphere and leaving a huge smoking crater in the ground..? If so, I'll keep the selector in Drive during the test.
#30
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OD = 4th gear. you can shift into 4th with or without the converter locked without damage/etc. if you want it disabled, just move the shifter into drive/3rd.
yes, you can just use a rocker/toggle to disable the TCC. wire it in series with the PCM'* command wire, flip it to the closed position, the TCC will act normal. flip it to the open position and the TCC will never engage until the switch is closed.
alternatively, if you wanted to force the TCC on at certain points, you could do that as well. keep in mind the TCC cannot be forced on in 1st gear based off of the hydraulic schematics i've seen, so if you drop speed down too far, it should kick out when you drop into 1st, though your engine may stall before that point.
you won't damage the transmission directly by disabling the TCC, though you will likely experience increased trans fluid temps (not an alarming amount, but noticable). almost certainty that your fuel economy will drop as well.
if i were you, i'd just try out throwing the shifter into D/3 and drive that way when necessary. pretty good chance that you'll be making enough power in 3rd with the TCC locked to maintain speed since the gearing difference between 3rd and 4th is 30%(meaning you'll basically have 30% more torque at your disposal). 3rd with the TCC locked will give almost all of the temp/MPG benefits of 4th/TCC, but with less torque reduction due to gearing.
yes, you can just use a rocker/toggle to disable the TCC. wire it in series with the PCM'* command wire, flip it to the closed position, the TCC will act normal. flip it to the open position and the TCC will never engage until the switch is closed.
alternatively, if you wanted to force the TCC on at certain points, you could do that as well. keep in mind the TCC cannot be forced on in 1st gear based off of the hydraulic schematics i've seen, so if you drop speed down too far, it should kick out when you drop into 1st, though your engine may stall before that point.
you won't damage the transmission directly by disabling the TCC, though you will likely experience increased trans fluid temps (not an alarming amount, but noticable). almost certainty that your fuel economy will drop as well.
if i were you, i'd just try out throwing the shifter into D/3 and drive that way when necessary. pretty good chance that you'll be making enough power in 3rd with the TCC locked to maintain speed since the gearing difference between 3rd and 4th is 30%(meaning you'll basically have 30% more torque at your disposal). 3rd with the TCC locked will give almost all of the temp/MPG benefits of 4th/TCC, but with less torque reduction due to gearing.