Increased performance after disabling TCM learn.

[Mr Big]

I read about disabling the TCM learn feature, using Forscan. I was having some weird shifting issues, so I decided to try it.
Now, my vehicle has much more low-end torque, shifts faster and tighter and downshifts instantly when rapid acceleration is needed.
It feels like I had custom tuning done. Performance is doubles, especially at the low end.
NOTE: When using Forscan, backup your vehicle before making any changes and use at your own risk.

 

[LokiWolf]

TCM Learn will have ZERO effect on power. ZERO. It will definitely change the behavior of the Transmission, and could allow lower gears to be held, and TC lockup to behave differently. TCM Learn can be a REAL PIA there is no doubt. Most of the time if I have issues, a simple reflash when I was tuned, or triggering a relearn with FORSCAN fixed the issue.

 

[Mr Big]

TCM Learn will have ZERO effect on power. ZERO. It will definitely change the behavior of the Transmission, and could allow lower gears to be held, and TC lockup to behave differently. TCM Learn can be a REAL PIA there is no doubt. Most of the time if I have issues, a simple reflash when I was tuned, or triggering a relearn with FORSCAN fixed the issue.

I agree it has zero effect on power, but because of the shift points being more accurate and pressures being set to factory settings, the vehicle performs way better, low end torque is more aggressive, (1/4 throttle and it takes off fast), and yes it holds the gears longer, instead of shifting too soon. I was doing what you are doing and it got to be a pain, plus the slippage issue. It's not as smooth as when it learns for a while, but it's also not as sluggish, kind of like I installed a shift kit. It's sort of in between normal and sport mode. It has more aggressive gearing and shift tightness, but it doesn't hold the lower gears when tapering off to 40 to 50mph, and it doesn't affect the steering and shock ride, like sport mode does. My main reason was because of the occasional slippage and slamming into gear. The latest recall may have fixed that issue. But I like the way it performs better now, so I'll keep it off for a while.

 

[Patri8]

What MY range does this affect? I have a 2021 I bought new and seems to have increasingly developed the issues this programming or deprogramming is purported to fix.

 

[LokiWolf]

What MY range does this affect?

Huh?