WOT TCC lockup for 4L80 not applying consistently

[Just Chuck]

P59 from 2004 Escalade, Foxbody Swap DBW , 6.0 , 3.73, 4L80, Segment swapped since the Escalade was a 4L60 originally. Circle D 4C triple disk converter, about 4400 stall.

Last time at the track the car was running 11.6-70 at 114-116. Best pass of the day was the converter locking at 105mph, even though I'm commanding lockup in 3rd at 97mph. On the next pass I lowered the lockup to 95mph and it didn't lockup till about 113mph just before the finish. HRP_Jun4.hpl is the log file with a good lockup.

The next log file V13_1.hpl is a pass in "mexico". From about 60mph, it makes the 2-3 shift and up to about 114mph without lockup ever coming on even though I commanded it at 95mph.

I'm OK if I have to fudge my commanded lockup 10mph early or what ever, but lockup seems to have a mind of it's own.


HRP_Jun4.hplv13_1.hplLTD_50lb_TBSS_90mm_EGR_100mmMAF13.hpt

[Just Chuck]

Haven't test my new theory yet, but this is what I' thinking.

Release TPS is set at 100% across the board. Since I'm at WOT aka 100% then I'm constantly commanding it to release. On the same tab, you have "High Speed TPS High". I currently have it set to 0% as this prevents the converter from unlocking when you let off the gas. Stock was 4%. I'm going to set it to 94% so above 94%, minimum throttle mode will be disabled above that. My high speed VSS is 86 MPH so the unlocking when letting off the gas should be unaffected at normal speeds.

I'll hopefully test it tonight when the roads in Mexico open back up.

[anniversaryss]

I wouldnt be surprised if that works. Unless you have a converter that can handle wot lockup most people dont.

[dzlunlim]

Why are you waiting so late to lock the converter? I assume you have a multi disc converter.

[Just Chuck]

Triple disk converter. It will handle the lockup. It?s an NA motor is the reason I don?t lockup earlier. But to that point, I plan to hit the dyno and make some passes with the converter locked and unlocked. Where ever the graphs intersect will help determine and optimal lockup point. Of course it all hinges on being able control the lockup.

[Just Chuck]

I think I figured it out. After all my changes nothing was helping so on a whim, while driving around mexico without the laptop hooked up, I hit at about 60 and ran it back up to 110. Commanded lockup at 95 and lockup seems to catch at about 105.

Thinking back to lockup at the track, I was logging TCC mode, but then I started to decrease the polling interval so I could get a better idea when things were happening. When things started happening later I added more TCC channels and decrease polling intervals on all of those which just made things worse. Not sure why VCM scanner would mess with lockup, but I have noticed that when I have vehicle control and special functions open, lockup stops working even at part throttle. My friend who owns a transmission shop also told me some Dodge vehicles have lockup weirdness when his snapon scanner is connected.