Info: TCM tuning

Mike L.

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Aug 12, 2006
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Mike, I mean no disrespect towards you as I think you are extremely intelligent when it comes to the Allison, but you admittedly know nothing about EFILive. I'm not looking for any secrets, but I have played with just about every table in an LBZ ECM and many in the TCM. I have not seen any that have a big effect on shift quality either good or bad. As I stated earlier, when my transmission was stock I was having a problem with a no shift at WOT and a nasty defuel when the truck hit the rev limiter. I was even having a bit of a problem with it after the trans was built. I even went so far as swapping ECM and TCMs with IdahoRob and still had the same problem. The second time I had to replace the C1s, the shifting got better for some reason. I have no idea why, but it did. If someone wants to show me a table or tables that will change shifting and defuel on an LBZ, I would love to be proved wrong, but until then, I have to believe that there is some other reason people who sell tunes are posting what they are.

Josh
Do you remember what I told you when you went into your Alli? What did you find? You wonder why it worked better? Slipping C1 will have an effect big time.
Your post made my point exactly. There is not much of anything EFI will do for your trans except give you the opportunity to screw it up.
The point that is being made here is fueling. This is where you are going to make a difference in your shift. Why are you guys so stuck on the TCM and the stupid B&M type shift? Those days are gone. Shifts should be smooth and quick. Hard shifts are tie ups.
Seems no one is getting this.
Yes you are correct that I have not played with EFI. Why would I? If I need a tune or a mod I have Tony, Pat, Guy, Chris to do it for me. Think there is someone better? Rob has helped me as well and Brayden also.
You srill can't do much of anything with the TCM. If you took the time to look at the operation of the Allison electronics you would see that there never will be much you can do.
 

racinmike77

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Sep 14, 2008
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Yes you are correct that I have not played with EFI. Why would I? If I need a tune or a mod I have Tony, Pat, Guy, Chris to do it for me. Think there is

I have a TCM tune from one of the above stated and It has modified D5197/D5196 tables. Rpm limiting disabled:confused:
 

JoshH

Daggum farm truck
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Feb 14, 2007
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Josh
Do you remember what I told you when you went into your Alli? What did you find? You wonder why it worked better? Slipping C1 will have an effect big time.
Your post made my point exactly. There is not much of anything EFI will do for your trans except give you the opportunity to screw it up.
The point that is being made here is fueling. This is where you are going to make a difference in your shift. Why are you guys so stuck on the TCM and the stupid B&M type shift? Those days are gone. Shifts should be smooth and quick. Hard shifts are tie ups.
Seems no one is getting this.
Yes you are correct that I have not played with EFI. Why would I? If I need a tune or a mod I have Tony, Pat, Guy, Chris to do it for me. Think there is someone better? Rob has helped me as well and Brayden also.
You srill can't do much of anything with the TCM. If you took the time to look at the operation of the Allison electronics you would see that there never will be much you can do.
You missed what I said. I said I was still having problems after I went into it the first time. It wasn't until the second time I had it apart that it started working well. I can't tell you what changed between the first and second time, but the trans has been shifting great since then. Also, I'm not trying to get any firm shifts or anything like that. I have never tried to eliminate defuel either. I did not adjust things in the TCM to get firm shifts. I just wanted it to shift when it was supposed to. The point I was making is I don't believe there is much if anything that can be done to eliminate defueling on an LBZ during shifting short of logging full throttle shifts, watching what torque value it defuels to, and going into the fuel to tq ref table (B1102) and raising the fuel quantity at those torque values or raising pulse width so when fuel quantity drops on a defuel the pulse doesn't. I want one of the people saying it can all be adjusted in the ECM to show me because I've played with it all and haven't seen the proof in the logs. I want someone to make a tune that doesn't drop the tq ref number and make a log of tq ref and RPM to show me it doesn't drop on a shift. Until then it all sounds like marketing to me.
 

lotsofmiles

Father of the Van
Dec 4, 2008
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Josh
There is not much of anything EFI will do for your trans except give you the opportunity to screw it up.

You srill can't do much of anything with the TCM. If you took the time to look at the operation of the Allison electronics you would see that there never will be much you can do.

Here is a dumb rookie efi user (me) question for you

I know this thread is about defueling shifts, etc..

But, I was trying to make a tune for better mpg's when I'm driving without a load. Mostly highway miles. I lowered the speed where it shifts into 6th, partial throttle up/down shift only, by about 5mph iirc, just trying to get it into top gear faster. Should I put it back to stock? Am I asking for trouble or should that be ok?

Seems to be fine, not lugging the engine. I know its going to shift sooner and drive accordingly
Thanks Mike
 

duramaximizer

#1 Abuse Enabler ;)
May 4, 2008
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Here is a dumb rookie efi user (me) question for you

I know this thread is about defueling shifts, etc..

But, I was trying to make a tune for better mpg's when I'm driving without a load. Mostly highway miles. I lowered the speed where it shifts into 6th, partial throttle up/down shift only, by about 5mph iirc, just trying to get it into top gear faster. Should I put it back to stock? Am I asking for trouble or should that be ok?

Seems to be fine, not lugging the engine. I know its going to shift sooner and drive accordingly
Thanks Mike

No, your fine.
 

BIG DIPPER

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Nov 6, 2006
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You missed what I said. I said I was still having problems after I went into it the first time. It wasn't until the second time I had it apart that it started working well. I can't tell you what changed between the first and second time, but the trans has been shifting great since then.

I think that's when you called me......:rofl:
 

BIG DIPPER

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Nov 6, 2006
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Until then it all sounds like marketing to me.

I didn't do the quote thing the way I wanted, but......

Josh, I did talk to you and think you realize that I don't BS. Truth hurts and so does spending money twice. I can assure you if you knew more about this transmission and how it was built, you would be blown away at the fact that it twisted the splines off.
 

JoshH

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Yes you did, George, and I was very grateful for your input. Please don't think I mean that TCM tuning can't hurt transmissions. I do believe it, and I am not saying that the tuning done in the TCM or ECM on this truck is what caused the failure. What I don't agree with is that it is possible to make a 6 speed have no defuel signal by making a few adjustments in the tuning. I have already said it is possible to make the trans not defuel, but I have never seen a way to prevent the tq ref number from dropping on a shift. I will admit that I don't have a lot of experience with the LLY and LB7 tuning, but based on what I've gone through with my truck and it's tuning issues, I feel I'm pretty knowledgeable on tuning for the LBZs. I don't think I'm the best by any means, but I feel I have a pretty good grasp on what different tables do and how they change things.
 

duratothemax

<--- slippery roads
Aug 28, 2006
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whats with all the trans refreshes/blow ups/issues going on? I have almost 100k miles on my old-skool suncoast IV, twins, had a built motor, etc. Ive been running my own TCM tuning (with some fairly decent changes to the shift timing and torque tables) forever. Knock on wood the only thing ive had to do to the trans is refresh the converter. Maybe im just lucky in the trans dept?

ben
 

JoshH

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whats with all the trans refreshes/blow ups/issues going on? I have almost 100k miles on my old-skool suncoast IV, twins, had a built motor, etc. Ive been running my own TCM tuning (with some fairly decent changes to the shift timing and torque tables) forever. Knock on wood the only thing ive had to do to the trans is refresh the converter. Maybe im just lucky in the trans dept?

ben
Maybe it's cause you already used up all your bad transmission luck when you were building it... :D

You gotta have good luck somewhere.

edit: my truck likes to eat C1 clutches for some reason. I don't know why, but the last two times it has happened it has been at the track, on a hard launch, with the Co-Pilot in full race mode (aka converter locks at the 1-2 shift), with my heavy H2s and mud tires on the truck. I spin on the launch then catch traction on the 1-2 shift with a locked converter and the C1s always end up being the weak link.
 
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MMLMM

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Mar 2, 2008
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The only change I would consider not damaging would be to copy the 3250 rpm row for table D5196 and paste it into rows 3400 rpm and 3600 rpm.

Messing around with the other areas of the table will only have you chasing your tail for part throttle shifts.

RPM changes for sled pulling, 1st gear delete is all fine. I change those for my customers and it works just fine.

The key to shifting an Allison properly is 95% ECM and 5% TCM tuning, if you have the tq values and tq limited injection quantity correct it will shift just fine, but other tables effect it, the wrong values in the main injection tables for fueling or the throttle table will cause you to chase your tail if you make a mistake in there.



I'll be back down at some point again.

;)

thank you, I wasnt sure to post my take on this yet, but its funny I just had a customer call after reading this thread freaked out. I too add some stock values 90-100% in this area. I also play with shift points and thats about it. SO far it has worked well and no issues.

When I raise shift points I like to do it in a %. adjust the rpm by a percent to find the correct rpm I want, then adjust the speed by the same %. That way there no trying to figure it out with math. This has helped and seems to be having good results.
 
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blackdeath

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Jun 24, 2009
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ive raised my my 1-2 2-3 3-4 shift point by 5 km, thats it. this only in tow haul ,that should be ok right?
 
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05_LLY

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Aug 7, 2006
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whats with all the trans refreshes/blow ups/issues going on? I have almost 100k miles on my old-skool suncoast IV, twins, had a built motor, etc. Ive been running my own TCM tuning (with some fairly decent changes to the shift timing and torque tables) forever. Knock on wood the only thing ive had to do to the trans is refresh the converter. Maybe im just lucky in the trans dept?

ben

Im in the same boat there, 4year old SC 4, only trouble has been a torque converter and a pressure switch, i raise shift points, and raised the TQ a bit in the ecm but all is good so far!
 

othrgrl

Diesel Addiction Owner
Mar 10, 2008
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Im in the same boat there, 4year old SC 4, only trouble has been a torque converter and a pressure switch, i raise shift points, and raised the TQ a bit in the ecm but all is good so far!

whats with all the trans refreshes/blow ups/issues going on? I have almost 100k miles on my old-skool suncoast IV, twins, had a built motor, etc. Ive been running my own TCM tuning (with some fairly decent changes to the shift timing and torque tables) forever. Knock on wood the only thing ive had to do to the trans is refresh the converter. Maybe im just lucky in the trans dept?

ben

How often do the 2 of you race, what kind of power are you putting down, and what kind of times have you run. The higher the power and the more passes you make the more your problems are going to come to the surface. Add 200hp to Wendy and that TCM tune that's been mentioned might take out the trans in 2 passes.
 

TrentNell

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Jul 7, 2008
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but I have never seen a way to prevent the tq ref number from dropping on a shift.

Josh its not really nec to have the torque # change or not change during a shift ........... the torque # after all is just a fictional # used for fueling reference .

for myself i am not a tuner so i have no clue whats best . All i have done is talk with Mike, and Rob who is doing my tuning and trust there judgment and so far my stage 3 is still holding strong and shifting very well . I will say that at the power level i was at i could not get that good of shifts on my own tuning . and yes some of the basic fueling tables especialy pulse width can change shifting .
 

GMC_2002_Dmax

The Still Master
I am going to help you all out here.

There is a conversions table in EFI-Live, it is a folder and it is clear as day, it is above the information, top right of the screen.

You can use this table to import a fueling table, timing table, torque table and then play around with the values without screwing the real table. Then when you have the values where you want them you can copy it back into the real table.

This is also important for adding or subtracting values from two different tables, two tables that you might not think you can compare you can even if they are different tables in the tune files.

If you alter throttle based injection quantity it will screw up torque limited injection quantity, this is a fact, if you alter base torque it can alter the de-fuel on the shifts.

If you have a huge disparity in the main injection pulse width tables from mm3 row or in adjoining cells and you follow the de-fuel with the scan tool link you can see where you may have to add or take away pulse width to correct a bad de-fuel or a over fuel on a shift.

Most people make the mistake of altering the throttle table first to get more fuel without altering the main injection pulse tables, if you go down that path you might someday get a good shifting tune, you may never, but that table is the key to everything else in the tune, that tells the ecm where to look, that and fuel pressure base on the LB7/LLY ecms. That is your right foot asking the truck to do something and it responds by looking up fuel MM3 and from there all other tables link for timing, pilot timing, pilot pulse, etc.

As far as the transmission,

When you alter the tq values in the TCM you have now upset the request for a proper de-fuel, when the request is wrong you now have two problems you will be chasing. one is an incorrect request for de-fuel if you eliminate it in the tune or raise it up the defuel will never be correct, two is you may have removed some of or all of the ability for the transmission to make a clean shift without tying up three clutches at once.

The shifting is by far the most difficult aspect of tuning, it took me almost a year to figure out how it all works, now I spend very little time on it because it's easy for me to fix it.

Tony
 
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E.carter

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Feb 16, 2008
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Learnig and getting confused at the same time. I will never be a tuner and or try. I will leave that to the guys that have a passion for it.