Questions about my 6l80 scanner log (2013 Silverado 1500)

[Wasil85]

I've noticed recently some funky behavior with my trans, and I have a new (used/reman) TEHCM from Transend that according to them is compatible with my OEM OS. Replacement TEHCM is GM #24265260 - Original TEHCM was GM 24265259.
Engine is a 5.3 LC9 with 2.3 Whipple, Truck Norris cam, ported PRC heads and all the bolt-ons.

Trans upgrades-Sonnax Reman valve body, Sonnax pressure regulator valve, Sonnax boost valve and high RPM Sonnax pump slide spring in the pump.
Circle D Level 4 rebuild with 2800-3000 Circle D 265mm converter. All clutch pack clearances were within CDT specs and unit passed the air checks before fully reassembled and put back in truck.
Overall driveability isn't really an issue other than this odd behavior since trans went back in. Have done tune revisions and Fast Adapt Resets, Presets, and Fast Relearns each time I adjusted oncoming pressures and whatnot. But overall it's only been a couple weeks, so maybe it's still learning/adjusting?


But I was hopeful someone with more knowledge and expertise to take a look and let me know if this looks/sounds like a mechanical issue, tuning issue or even some kind of electrical or software issue.. Because really the main thing that concerns me, is that I see while at idle in park, PCS 2 command pressure & PCS 4 command pressure blip 41psi at the same time randomly. You can see this in the first couple seconds of the log as an example, but it does it in these conditions each time.

Also, I'm not trained well enough yet to read into the PCS command pressures throughout all the other gears and driving conditions, so maybe the blips are actually the least of my concerns? haha

Attached are a copy of my current tune file and latest log from this morning. Hope to hear from someone that can tell me what's going on with the blips in park at the very least.Whipple NW 103 3.75 Pulley FIC 1000 Walbro 525 35's CDT 4.hpt24-11-13 08-25-56.hpl

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Nothing yet? I'm new here, procrastinating my purchase(I see credits for the TCM, separately for the ECM, &want to be sure I get exactly what I need) and trying to learn as much as I can but posts are all over the place. Your mods are similar to what I've got planned in the future to my 5th gen silverado

[TransGo Robert]

The pulses you see are normal, those are air purge pulses. Is hat all that had you worried or is something not feeling right? You said: "I've noticed recently some funky behavior with my trans" but aside from the solenoid pulse you did not mention anything else, so I am not sure if that was the "funky behavior" or not.

[Wasil85]

Thank you for your reply TransGo Robert! Was hoping to hear from you specifically to that question/concern of mine sir.
Well yes and no.. I am thinking it might just boil down to all of the new components and the trans relearning itself. There have been some strange shift characteristics and feels in the pedal, but it seems to be settling more and more as each day passes.

Frankly, however, with you now assuring me that those pulses aren't indicative of a cross leak somewhere (I was actually concerned it may have had something to do with the pressure switches on the TEHCM), I am now just wondering if Oncoming Volume Presets or other Volume parameters need to be adjusted. Most specifically in the 4-5-6 clutch hub because of the physical changes to it vs stock.

If any 6L80 tuning experts read this and know for certain that with the CDT 45 tooth, 4-5-6 billet shaft/hub (which eliminates the OE dampener) and Powerglide style clutches requires some specific volume adjustments to accommodate for this, I would gladly pay for your time and expertise if you know what these values should be and can help a brotha out. I cannot find the info online anywhere and CDT recommend I contact a specific someone for this info. Only problem is it looks like an approximate 1 thousand dollar paywall in place to talk with him about custom tuning lol

[TransGo Robert]

Thank you for your reply TransGo Robert! Was hoping to hear from you specifically to that question/concern of mine sir.
Well yes and no.. I am thinking it might just boil down to all of the new components and the trans relearning itself. There have been some strange shift characteristics and feels in the pedal, but it seems to be settling more and more as each day passes.

Frankly, however, with you now assuring me that those pulses aren't indicative of a cross leak somewhere (I was actually concerned it may have had something to do with the pressure switches on the TEHCM), I am now just wondering if Oncoming Volume Presets or other Volume parameters need to be adjusted. Most specifically in the 4-5-6 clutch hub because of the physical changes to it vs stock.

If any 6L80 tuning experts read this and know for certain that with the CDT 45 tooth, 4-5-6 billet shaft/hub (which eliminates the OE dampener) and Powerglide style clutches requires some specific volume adjustments to accommodate for this, I would gladly pay for your time and expertise if you know what these values should be and can help a brotha out. I cannot find the info online anywhere and CDT recommend I contact a specific someone for this info. Only problem is it looks like an approximate 1 thousand dollar paywall in place to talk with him about custom tuning lol

I can't help with the tuning part unfortunately, but let me just clarify something here. What you see for the pressure control solenoid data is not a feedback, that's just desired pressure based on the computer electrical command of the solenoid. You could have huge cross leaks in there and you would never be able to tell looking at the log, there is no pressure transducer in that unit so it has no way to know. The pressure switches only monitor the valve position, they are not in the actual pressure circuit going to the clutches and brakes in the transmission.

[Wasil85]

Ok, thank you for the clarification Robert.