A40 TCM Tuning

[08lmm72mm]

Hey guys,

I'm modifying my stock TCM tune so it has slightly higher shift points going into 5th and 6th gear so my truck doesnt bog and blow black smoke with my turbo. Now I've adjusted my part throttle 2-3, 3-4, 4-5, and 5-6 up shifts and the 6-5, 5-4, 4-3, and 3-2 downshift to how I want them in Pattern A, now I'am curious if i need to adjust anything in the TCC Apply/Release speeeds for each gear as well?

My goal here is to have the truck shift a little higher in part throttle driving and not have the truck shift into 5th until 56mph and not have 6th shift until 75mph. The reason is with 35s and the 72mm turbo is that it shifts into those gears too early for where the turbo is happy. Thanks for any help.

 

[Dozerboy]

You don't need to mess with with the apply and release speeds. Make sure you test out your changes IIRC some of those shift pattern labels are wrong.

I don't think I changed up shift on mine. I just made it down shift on anything over 50% throttle.

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[08lmm72mm]

Sounds good I'll give that a try thanks.

 

[Chevy1925]

i raised my TCC lock up 5mph from stock. i drive around town at 50mph and being locked at that speed meant i was at 1500rpm in 5th gear. leaving it unlocked there let me get on top of the turbo real quick before lock up happened for shit like getting through a yellow light or getting around someone. no smoke and way less lag that way.

 

[monster50iii]

I like my 5th tcc apply a bit higher than stock. Also, make sure you look at the graph above the numbers WHILE the correct column is highlighted and make sure you have a nice smooth curve.

 

[08lmm72mm]

Thanks guys for the feedback! I'll definitely try out the suggestions!

 

[dylon333]

You don't need to mess with with the apply and release speeds. Make sure you test out your changes IIRC some of those shift pattern labels are wrong.

I don't think I changed up shift on mine. I just made it down shift on anything over 50% throttle.

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Any chance you would be willing to share the tune? Or even a screen shot of the down shift table? I think I did it right but worried about screwing It up would like to see what you did, or I could send you my file aha see what you think


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[Chevy1925]

Any chance you would be willing to share the tune? Or even a screen shot of the down shift table? I think I did it right but worried about screwing It up would like to see what you did, or I could send you my file aha see what you think


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As long as you didn

 

[dylon333]

Ok great thank you.


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[dylon333]

Just an update. Tried to make it down shift at anything over 50% throttle in 5 and 6 and I did some thing wrong. It would get to to 5 and when it was time to go to 6 while under load it wouldn

 

[JoshH]

You need to make sure the speeds in your upshift table are higher than the downshift at the same throttle position.

 

[TheBac]

....waiting for the inevitable "made a horrible mistake, had a tie up and now have to rebuild the trans" thread.....

I personally would never play with the upshift/downshift tables.

 

[D_Ferrante801]

....waiting for the inevitable "made a horrible mistake, had a tie up and now have to rebuild the trans" thread.....

I personally would never play with the upshift/downshift tables.

As long as hes not playing with shift timing hes not going to really harm a thing. Part throttle upshift and downshift adjustments are awesome when done properly for larger chargers and tires...

 

[Chevy1925]

....waiting for the inevitable "made a horrible mistake, had a tie up and now have to rebuild the trans" thread.....

I personally would never play with the upshift/downshift tables.

Like Ferrante said, it wont hurt anything. either the shift will happen or it wont and throw codes because speeds arent matching correctly.

its the timing or oncoming and off going clutches that can kill the trans in a hurry

 

[dylon333]

I

 

[2004LB7]

Shouldn't you be adding mph not taking it away? I thought you where looking to raise your shift points?

 

[dylon333]

Um. I want it down shift sooner. Maybe I

 

[dylon333]

I think your right so I lowered the down shift and raised the up shift but still not don

 

[Chevy1925]

raising speed on downshift will make it down shift sooner as more throttle is given. raising speed on upshift will cause the upshift to delay later.

Sooner downshifts = up speed according to what throttle input you want
later downshifts = lower speed according to what throttle input you want

sooner upshifts = lower speed according to what throttle input you want
later downshifts = up speed according to what throttle input you want

you need to be logging and watching throttle position, vehicle speed, and current gear. modulate the throttle where you think you want the downshift and tag by hitting F3 or F4 while logging (cant remember what F button it is, been a long while but a white line appears during the log so you know right where you want it). change the downshift to match that speed and throttle input and smooth the ones above it out. If downshift speed is higher than upshift speed at the same throttle input, it aint gunna upshift and will throw codes. make sure upshift is at min 1mph higher.

the closer you make upshift and downshift together, the easier it is for them to shift back and forth at the same throttle input (assuming upshift stays constant right now). as they spread apart, downshifts become harder to achieve to the point they wont happen.

 

[TheBac]

I guess I got my tables mixed up......my apologies.
I always ran the basic 01 OS and never had any problems or issues.

Carry on.