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View Full Version : 3-4 upshift table issues.



2007 5.9
January 9th, 2012, 04:21 PM
Hey everyone, have a couple of questions that some of you might know the answer to and some of you might learn from when its answered correctly.

i am trying to control when my truck goes through its 3-4 upshift schedule.

I am trying to command 3-4 upshift at 2000-2200 and have adjusted my axis tables accordingly (to my knowledge) but for some reason, the ECM still likes to dictate 3-4 upshift on its own.

Here are 3 pictures of my tables in various axis settings and Throttle % settings..

This one I tried to get 3-4 at 2200 rpm TOSS at 1% throttle

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This one I tried 3-4 at 2200 TOSS at 30% Throttle

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Then this one at 2100 TOSS at 33.5%

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What I am looking for is like a on/off switch...I want 3-4 at 2200 TOSS and no a moment sooner...but it seems that no matter how I command it with different TOSS axis or Throttle %, the truck still has no rhyme or reason as to when it goes from 3-4.

Sometimes it shifts at 1500 TOSS and sometimes at 2000 TOSS...but never the same way twice.

Anybody play with this and get it to work right??

MQ105
January 9th, 2012, 11:13 PM
What does your 4-3 downshift table look like? Have you changed it so as not to conflict/overlap with the upshift?

Mine seems to upshift no lower than 1600 set like this:

http://i151.photobucket.com/albums/s122/mq105/3-4TOSS.jpg

However, if I run in 3d gear at steady speed for more than 4-5 seconds, the TC locks. Then, if I gradually accelerate, the 3-4 shift happens in lock-up. Immediately thereafter the TC unlocks. If I am steadily accelerating everything works fine and the TC does not lock in 3d gear. My TCC 3d gear table is set as stock, which is to stay unlocked below 2500 RPM.

I have an '07 which has the T/H mode and O/D off mode. In O/D off mode the TC locks in 3d gear above about 1550 rpm at steady speed. I think there is some other table we don't yet see that controls this, and therefore explains the 3d gear TC lock-up I see when not in O/D off mode.

2007 5.9
January 10th, 2012, 01:41 AM
My 4-3 DS happens at 1900 perfectly on decel....

I have ran into the situation you describe with 3rd lock then 4th apply then tc unlock...that has happened to me several times.

Mt 3rd TCC lock is set to happen as low as 1200rpm TOSS but happens as you describe at 1550-1600 rpm TOSS.

I'm guessing that there is still more trans tables to be found as well.

skneeland
January 10th, 2012, 02:13 AM
ive seen it mentioned a few times that changes to the Axis definitions for some of the transmission tables arent actually changing anything

2007 5.9
January 10th, 2012, 02:15 AM
That would correlate to my 3-4 up shift table but not for my 4-3 downshift tabke

MQ105
January 10th, 2012, 08:52 AM
Les, have you tried to alter the table while leaving the axis stock? I haven't yet, but it's next on my test list. Something like this:

http://i151.photobucket.com/albums/s122/mq105/3-4TOSS-01.jpg

2007 5.9
January 10th, 2012, 09:20 AM
I have not..maybe if the tune I loaded this morning at work doesn't pan out on the way home...maybe I'll try that route.