ZF8HP2 separate tune

[wadejesu]

has anyone had any luck, tuning TCM only, I have 2019 Ram 3500 6.4 8spd and trying to get firmer shifts, according to Brian@HPT you should be able to read, edit and write TCM only even if ECM is NOT UNLOCKED. I have Smart cable installed, latest stable and beta versions. I am able to edit and read TCM but not ECM, not sure why ECM is unlocked but I get x35. When reading stock files I skip reading ECM and read TCM only after writing TCM only I get U402 and U01110 DTC,s

[spoolboy]

Yes, tuning TCM only is no big deal while leaving the PCM locked and unmolested, but if you want to reduce torque management but leave it safely enabled, you need to tune the ECM side. You can still do a lot in the TCM only, but some of the torque management will be inaccessible.