wot 2-3 shift on limiter

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I am running into trouble with a 6.0 4l80 combo hitting limiter on 2-3 shift it is not being commanded I've tried everything i can possibly think of wot set to 4800 I've tried 4000 it just wont command until 93mph I am running it in 4 low 5.13 gears reading from trans output vss wondering if its just not possible for the pcm to shift fast enough. tune and log posted 0411 512k cos

[joecar]

I'll look at your tune when I get home.

In your tune did you correct the speedo for your gear/tire...?

~Moderator~

[[email protected]]

I'll look at your tune when I get home.

In your tune did you correct the speedo for your gear/tire...?

~Moderator~

Yes but it reads wrong when I'm in low range which shouldn't bother anything I just sold my other jeep with the same setup but 4.10 gears and 1mb pcm that worked fine

[[email protected]]

If you look at the log commanded gear it's on limiter for a while before it even commands 3rd, pcm too slow? I'm stumped and I race up a snow hill in a week. might try changing to a 1mb. one thing I forgot to do was Dvt control I'll try that when I get home tomorrow.

[joecar]

The PCM is not slow, it's being fed incorrect data and/or its tables are incorrect.

~Moderator~

[[email protected]]

The PCM is not slow, it's being fed incorrect data and/or its tables are incorrect.

~Moderator~
So you obviously see something wrong in the tuning side of it? I've done a bunch of logging and tuning what should I be logging that I'm missing?

[[email protected]]

nobody? nothing surely there has to be a fix for this? I've searched everywhere Ive tried all I can find

[joecar]

Sorry, I have been delayed... I'm still looking thru your tune file.


What axle ratio and what tire size do you run...?

[[email protected]]

Sorry, I have been delayed... I'm still looking thru your tune file.


What axle ratio and what tire size do you run...?

I have 5.13 gears 35" tire like I Said before I am running 4 low but reading speed before transfer case. I have a race Saturday and am pulling my hair out. if I let off throttle slightly at the right time it will shift, any help would be much appreciated thanks

[joecar]

Your WOT upshift/downshift MPH values are upside-down, including the WOT 2->3/3->2 values

the downshift MPH has to to be lower than the corresponding upshift MPH
e.g. your D0930,31,32,64 are set to 60,60,66,30; your D0915,16,17,67 are set to 20,20,55,25; these are upside-down, this will prevent WOT upshift in any mode of the 4 modes.

Same with your PT 1->2 and PT 2->1 tables.

[[email protected]]

Your WOT upshift/downshift MPH values are upside-down, including the WOT 2->3/3->2 values

the downshift MPH has to to be lower than the corresponding upshift MPH
e.g. your D0930,31,32,64 are set to 60,60,66,30; your D0915,16,17,67 are set to 20,20,55,25; these are upside-down, this will prevent WOT upshift in any mode of the 4 modes.

Same with your PT 1->2 and PT 2->1 tables.

well i've been looking for something like that for a while but pretty much so frustrated looking just not thinking straight just changed some things accordingly try and report back in a few minutes thank you very much for taking the time out of your busy day to help

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just tried it still hit pretty hard but better i believe check my work different tune modified here is log and tune