cold low speed shifting hard
02-01-2006, 04:26 PM
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cold low speed shifting hard
I've got my trans settings just about where I like them except for in the morning when the trans is cold it shifts way to hard during the 1-2 shift with little throttle. It only does this when its cold, it's fine after it warms up.
I've tried backing down the 1-2 Upshift Pressure Mult vs. Temp vs. Gear, but it doesn't seem to help much.
Which one would be better to adjust:
Upshift Pressure Mult vs. Trans Temp vs. Gear
Or
1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque
And why?
I couldn't attach my tune here, so if you want to look at it go here; http://hptuners.com/forum/showthread.php?t=4668
I've tried backing down the 1-2 Upshift Pressure Mult vs. Temp vs. Gear, but it doesn't seem to help much.
Which one would be better to adjust:
Upshift Pressure Mult vs. Trans Temp vs. Gear
Or
1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque
And why?
I couldn't attach my tune here, so if you want to look at it go here; http://hptuners.com/forum/showthread.php?t=4668
02-01-2006, 07:00 PM
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GMs do that
Gm trucks do that when its really cold. It somehow helps heat the trans up faster or something like that. I heard this from a gm dealer. Im not sure exactly what he said tho, but its to do with warming the truck up faster.
Derek
Derek
02-01-2006, 09:18 PM
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No it was fine before I started messing with it and when I mean hard I mean tire barking hard. 
Seems like when ever I get the 1-2 softened up, it messes up the rest of the shifts too.
Seems like when ever I get the 1-2 softened up, it messes up the rest of the shifts too.
02-01-2006, 09:32 PM
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Well i took quick look at your trans tables. While i dont see much out of the ordinary for the temp-modifyer tables. But i must say you have one helluva aggressive line pressure settings.
Does your tranny have a shift kit installed?
Does your tranny have a shift kit installed?
02-01-2006, 09:58 PM
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Originally Posted by RoninsDenali
Well i took quick look at your trans tables. While i dont see much out of the ordinary for the temp-modifyer tables. But i must say you have one helluva aggressive line pressure settings.
Does your tranny have a shift kit installed?
Does your tranny have a shift kit installed?
Any thoughts?
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02-02-2006, 08:53 AM
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OK, i had a little bit of time to think this through here, and comparing the trans line pressure settings to some other bin's i have. I think i can confidently recommend two things you can try.
1.) Be aggressive in the 1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque table when reducing line pressure for the colder trans temp cells. Considering your low-torque values on the line pressure table are probably 2-3x greater than mine are i'd say its safe to be just as aggressive in toning things down a bit through the upshift modifier table.
or...
2.) Take out some of that low-torque linepressure from the main pressure tables for the 1->2 shift. Unless of course once the tranny is warm it shifts exactly the way you like it then i'd go back and re-read number 1
1.) Be aggressive in the 1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque table when reducing line pressure for the colder trans temp cells. Considering your low-torque values on the line pressure table are probably 2-3x greater than mine are i'd say its safe to be just as aggressive in toning things down a bit through the upshift modifier table.
or...
2.) Take out some of that low-torque linepressure from the main pressure tables for the 1->2 shift. Unless of course once the tranny is warm it shifts exactly the way you like it then i'd go back and re-read number 1
02-02-2006, 10:04 AM
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Originally Posted by RoninsDenali
OK, i had a little bit of time to think this through here, and comparing the trans line pressure settings to some other bin's i have. I think i can confidently recommend two things you can try.
1.) Be aggressive in the 1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque table when reducing line pressure for the colder trans temp cells. Considering your low-torque values on the line pressure table are probably 2-3x greater than mine are i'd say its safe to be just as aggressive in toning things down a bit through the upshift modifier table.
or...
2.) Take out some of that low-torque linepressure from the main pressure tables for the 1->2 shift. Unless of course once the tranny is warm it shifts exactly the way you like it then i'd go back and re-read number 1
1.) Be aggressive in the 1->2 Upshift Pressure Modifier vs. Trans Temp vs. Torque table when reducing line pressure for the colder trans temp cells. Considering your low-torque values on the line pressure table are probably 2-3x greater than mine are i'd say its safe to be just as aggressive in toning things down a bit through the upshift modifier table.
or...
2.) Take out some of that low-torque linepressure from the main pressure tables for the 1->2 shift. Unless of course once the tranny is warm it shifts exactly the way you like it then i'd go back and re-read number 1
Thanks, I'll give that a try.