LFX/6L50 trans tuning help needed

[EightMile]

I have a 2015 LFX/6L50 powertrain that I have put in a 2002 Blazer to roadrace in 24 hours of Lemons. It has the stock harness, ECU, TCM, and BCM. It also has the complete steering column, brake pedal assembly including booster ad master cylinder(no ABS).

When running the car in TUTD mode it will 3-2 downshift on its own and skyrocket RPM. I had some remote tuning help while at the track but was unable to cure the downshift problem.

Attached is the current tune and a log. At around 3min into the log, the car is in M3 accelerating and suddenly downshifts. Any help would be greatly appreciated.

roadrace_4.hpt
log_3_4_13_25.hpl

[KillboyPowerhead]

Compared to mine (2015 Camaro 1LT) the only real difference I see is under Shift Scheduling > Part Throttle Shift > Tap Up / Tap Down and Safety Shifts, tables 15006, 15306 and 15307 are zero'd out on mine, and I don't get any auto down shifting. Otherwise I have similar numbers to yours in the rest of the tables. Attached is a factory 2015 tune for comparison. Not sure if any other tables would cause this to happen, like under Torque Management. Does the dash display show that you're in manual ("M") before/during/after the downshift?

2015_Camaro_1LT_RS_Factory.hpt

[EightMile]

Compared to mine (2015 Camaro 1LT) the only real difference I see is under Shift Scheduling > Part Throttle Shift > Tap Up / Tap Down and Safety Shifts, tables 15006, 15306 and 15307 are zero'd out on mine, and I don't get any auto down shifting. Otherwise I have similar numbers to yours in the rest of the tables. Attached is a factory 2015 tune for comparison. Not sure if any other tables would cause this to happen, like under Torque Management. Does the dash display show that you're in manual ("M") before/during/after the downshift?

2015_Camaro_1LT_RS_Factory.hpt

Thanks for the reply...

I saw those tables too, but I'm new to this and was afraid to make changes that might hurt something. Now knowing that those tables are zeroed out on your tune it makes feel more confident in trying it. This is a "track only" car and testing is difficult but we have found a spot to test and this is the first thing we are going to try...

thank you

[EightMile]

Thanks for the reply...

I saw those tables too, but I'm new to this and was afraid to make changes that might hurt something. Now knowing that those tables are zeroed out on your tune it makes feel more confident in trying it. This is a "track only" car and testing is difficult but we have found a spot to test and this is the first thing we are going to try...

thank you

Oh by the way... the I.P. does not display the downshift...

[dromey]

Any update? I have a similar issue not quite the same as yours, but maybe your solution can help me still.