2013 Cadillac ATS 3.6 6l45 converter shudder.

Having an issue with the shudder at light throttle after warmup.
I'm a newby with HP tuners, can anyone tell me exactly how to disable the lockup to confirm that the converter is the issue?

Thanks in advance!

Butch

Post the tune file so we can see it.

No tune file yet. Before I start tuning, i want to determine if the tc lockup is the problem, and fix it.
Just need the table to go to and what settings to change.

Thanks!

I need to see the file to tell you what to change though. I don't have a file so I don't know what ECM table number it is yet.

All I can tell you is that it will be in the torque converter tab and there might be a table for gears 1-4 and 5th/6th. This is how it is on the 6L80e's in the trucks.

Attachment 101332

Here's a pic of the converter tab.

The Normal Apply table is what you will click in the top left hand corner.

That will display gears 1 through 4. Take each row and set it way high like 200 or 300mph. Then click the release table and put 199 or 299 for each gear. That will disable the torque converter in gears 1-4 forever. The same could be done for gears 5th and 6th if needed but you said it's a low speed shudder so gears 1-4 should be all that's needed.

Awesome, Ill give that a try!

Also correlate the gear change scheduling with the TCC apply/release.

If you don't want it to lock up then set the value to near max.

My only experience with TCC causing shutter was with a few older GM V6 cars (late 90's, early 2000's cars with 4speed) during the 3-4 gear change around 12% throttle because from factory they had the TCC overdrive apply in 4th gear 1 mph lower than the 3-4 shift. So the ECM wanted to lock up the TCC for 4th overdrive right before the 3-4 shift.

Thanks all for the tips!

First i disabled tc for gears 1-4. Had less shudder, but now showing up in 5th, maybe 6th. So I disabled 5th, shudder still there. Final option is to disable 6th. Success, no more shudder!!! So, no question it's the converter lockup. I think i'll just leave it all shut off. Car runs great, downshifts are way faster and throttle more responsive now. I'll probably change the fluid in the near future.

Look into a general search over the net on GM 6 speed shudder. It's not an uncommon complaint. I experienced it on a few rare occasions that I recall mainly happening shortly after startup during the Winter in an 08 CTS. I changed the transmission fluid, which was a little low along with the filter and it has been quite some time since I've experienced it. I have not made any tune changes as of yet, but have experienced the adaptive shift learning effect after logging some spirited driving, following months of light on the pedal driving.