6L80 bad slip/flare shifting from 3-4

[hjtrbo]

You're a fair way from fixing this with injector data. Just do what I suggested and go for a WOT 2-3 hit. If it doesnt hold the shift then she's all over. You've got plenty of commanded line pressure now at WOT.
You can play around with the injector stuff afterwards whilst saving for a rebuild and nursing the trans.

[GHuggins]

Yes trans damage is most likely done. All it takes sometimes is 2 or 3 slips and the clutches have had it. Your third gear clutch is what's slipping - albeit not bad, but it is slipping. You can try increasing shift pressure or lowering times, but this did just start so there's that. It may even be a pressure setting it has learned, but flashing the trans should have reset that.

The injector data is correct as long as you got the data in right.

I can still get the torque model closer for you - just email the log, but I'm afraid it needs mechanical work at this point. I'm afraid it was driven too long with the torque model off. This is why I say time and time again that just because fuel models are dialed in doesn't make the torque model right. Unfortunately this is the result.

[GHuggins]

Since it's already the way that it is give this one a try. Just made a bunch of changes to the transmission and one torque management change. Don't know with the way the torque model is if it'll work or not.

[TURBOSILVERADO11]

Since it's already the way that it is give this one a try. Just made a bunch of changes to the transmission and one torque management change. Don't know with the way the torque model is if it'll work or not.

Thank you, that was a lot of changes. I will try it in just a little bit and see how it does. Since it's showing the engine torque so high now does torque model need to be drop some if this tune works?

[GHuggins]

The torque model will need adjusting regardless. It may even be part of the problem now cause you can go too high with auto's so if you have downshifting problems, well.... Torque output most likely went up not only because of the torque model but also because I corrected your MAF curve. Again, why it needs to be dialed in even in SD mode.

[TURBOSILVERADO11]

Got about 14 miles on it right, I'll put a log on here tonight once it learns more

[TURBOSILVERADO11]

Here's two logs, 1st one is getting on it hard 2nd one is driving less than 50% throttle. It's mostly slipping going into 5th gear now unless its around 30% throttle. Felt good WOT but on the 2nd pull it pulled all the fuel again and added 40 degrees of timing. I only drove it about 40 miles since loading the tune and doing the rest preset so it's probably still learning.

tune test.hpl
tune test 2.hpl

[TransGo Robert]

Here's two logs, 1st one is getting on it hard 2nd one is driving less than 50% throttle. It's mostly slipping going into 5th gear now unless its around 30% throttle. Felt good WOT but on the 2nd pull it pulled all the fuel again and added 40 degrees of timing. I only drove it about 40 miles since loading the tune and doing the rest preset so it's probably still learning.

tune test.hpl
tune test 2.hpl

Yep unfortunately it is time to get surgery on that transmsision. Your 4-5-6 clutch pack is most likely metal to metal or the drum drum cracked but it does not seem to be bad enough to be a cracked drum. It does slip a little bit in 4th just before thh 4-5 shift under the right load, but it is obvious on the 4-5 at 40% throttle or so and it slips like crazy in 6th when the lock-up comes ON and then it clamps back on eventuality. it is much easier for the 4-5-6 clutch to hold in 4th because it is not the driving member unlike in 5th and 6th that's the only reason it does not slip like crazy in 4th. At least now it the commanded pressure and ramp up and down of the various friction element is correct. Be sure to have them put our TOW&PRO kit in there when you get it fix, with the kind of power you have it will make a huge difference on how long the transmission last, and should help you to the finish line a tad faster

[TransGo Robert]

Awesome, so for individuals say running a circle D that is horrible for lockup, this would help and help it to stay locked? Of course I know the trans needs to be changed settings wise too, but if something mechanical can greatly help then I'm all for it.

Also glad we have someone like yourself on the forum now. Really helps with things like this.

I had missed this reply until now. Nothing in any of our kits changes anything as far as the converter ability to stay locked. I deal almost exclusively with stock configuration and the problem is not with holding the clutch, it is the opposite, specially with aftermarket converters they just can't get the desired slip. Our valve makes it easier for the computer to control the slip more precisely. Now I am not familiar with any specific issue with Circle D converter and specially with issue where the clutch can't hold but if you give me details I am sure I can help. I don't want to highjacks this thread so feel free to message me directly if you want.

[GHuggins]

Yes, what he said. Afraid the damage was already done. That trans tune is running in some 1000hp builds and even very heavy builds. Should have quick firm shifts and no slips at all especially with your line pressure now. Torque model needs to be fixed, but either way the clutches in yours are slipping.

[hjtrbo]

I reckon there is a table missing in HP. It seems so weird to have to muck around with the torque model to get the line pressure right. Old school is the throttle valve. I reckon the GM engineers would have created an electronic version of it, and the corresponding table.

[TransGo Robert]

I reckon there is a table missing in HP. It seems so weird to have to muck around with the torque model to get the line pressure right. Old school is the throttle valve. I reckon the GM engineers would have created an electronic version of it, and the corresponding table.

Using the throttle never worked quite right on the few units it was used like the 700-R4, 200-4R and alike. Pressure needs to be adequate for the load, the throttle position matters much less. That's why units with vacuum modulator always worked better and lasted longer. Fast forward to modern time, the MAF and or MAP are what every manucature use to calculate the load and command the appropriate pressure.

[TURBOSILVERADO11]

Dang, that's what I figured. How much is it supposed to slip WOT? It's always been about 2000 rpm, is that about right or is that to much? Thanks for all the help!

[GHuggins]

Dang, that's what I figured. How much is it supposed to slip WOT? It's always been about 2000 rpm, is that about right or is that to much? Thanks for all the help!

Slip while shifting and slip while holding gear are completely different. Should have no slip while holding and reasonably a small amount while shifting. TM when not set up right or shift timing when not set up right will cause long slip times while shifting as well.

[GHuggins]

I reckon there is a table missing in HP. It seems so weird to have to muck around with the torque model to get the line pressure right. Old school is the throttle valve. I reckon the GM engineers would have created an electronic version of it, and the corresponding table.

There is something in the background. Take a 5.3's torque model and put it into a 6.2's cal. Guarantee the 5.3's numbers are much higher torque wise than the 6.2's and as we know that's impossible. Makes doing engine swaps a big ol' pita... Doing 2 right now that I've just about had to change every table in to make background tables work for the different engine's OS... Everything is affected from startups to transmission operation.

[GHuggins]

I had missed this reply until now. Nothing in any of our kits changes anything as far as the converter ability to stay locked. I deal almost exclusively with stock configuration and the problem is not with holding the clutch, it is the opposite, specially with aftermarket converters they just can't get the desired slip. Our valve makes it easier for the computer to control the slip more precisely. Now I am not familiar with any specific issue with Circle D converter and specially with issue where the clutch can't hold but if you give me details I am sure I can help. I don't want to high jacks this thread so feel free to message me directly if you want.

Circle D runs a whole lot of clutch clearance and part of the operation of the controller is to apply then bleed back off the hold pressure, kind of a constant fight by itself, then you throw the bigger clutch clearance into the equation and well things are just that much harder to get right. You wind up having to jack apply pressure and max pressure way up and then play with the regulator settings. For some reason every circle d seems different too, like maybe not as tight of controls in place?

[TURBOSILVERADO11]

Yeah, I know you don't want any slip when holding. But I just want to make sure it's not slipping to much when it's WOT.

[TURBOSILVERADO11]

Yes, what he said. Afraid the damage was already done. That trans tune is running in some 1000hp builds and even very heavy builds. Should have quick firm shifts and no slips at all especially with your line pressure now. Torque model needs to be fixed, but either way the clutches in yours are slipping.

Have you ever seen one pull all the fuel and put that much timing in at WOT? Also, it felt great not pulling any timing on the shift, It was pulling about 10 degrees before. You could feel the difference of no timing pull

[GHuggins]

Have you ever seen one pull all the fuel and put that much timing in at WOT? Also, it felt great not pulling any timing on the shift, It was pulling about 10 degrees before. You could feel the difference of no timing pull

You'll have to post a screenshot of what you're talking about on that one. I still haven't seen it in the log. Probably looked right over it. If it's happening during a shift that's just tm. Tm even when disabled will still be used if the transmission control module sees something wrong with a shift as a last ditch effort to save itself. Otherwise I'll need to be pointed to what your talking about in a specific log with a time stamp

[hjtrbo]

Also, it felt great not pulling any timing on the shift

Feels good, gives the back end a good wiggle, kills the trans too unfortunately. TM is necessary, especially with your power level. Greg is doing a good job for you. Next trans you will be right once he's finished.