Trans torque ratings?

[jakebrown617]

Some tuners (staff included) increase the Driver Demand torque numbers to exceed their vehicle's transmission max torque rating as defined in the model number. So by Ford, I believe that would be: 10R60 -> 600 Nm ~= 443 ft.lb and 10R80 -> 800 Nm ~= 590 ft.lb., as examples.

At what point beyond this limit should we expect trans lifespan effects? I've heard folks start looking at trans upgrades when running straight E85 due to the massive gains possible there, but I'm curious if there is a rule of thumb for just how much beyond the rated limit we should be going in our tunes. Thanks!

[Perna00]

Based on “the tuning school”, the 10r80 is rated up to 590 ft lb before you start to have adverse effects on longevity. Technically the lower you limit it, the less wear it will incur. My goal is to get the engine tuned for performance and then limit the shift torque numbers to help control wheel spin as long as it’s below the 590. Everyone will have their own opinion though.