anyone have trouble with their torque converter not locking or coming unlocked often during normal driving and cruising?
this is on a 6th speed allison, 2008 LMM 3500HD dually. everything is stock except the tires at 245/75/17, DPF delete and my tuning.
the problem i am having is that it does not like to lock the converter. even when lightly cruising around town or on the highway it will not lock on its own. if i play with the accelerator i can get it to lock but the slightest increase or decrease in the pedal will unlock it. when in cruise control it will not lock at all unless i take it off of CC and play with the pedal to get it to lock then hold it while engaging CC. it then seems that it will hold the converter locked through light grades but will instantly unlock it if it slightly more gradient or on all down hills.
i am not even trying to get it lock under power just daily driving and it seems like it is scared to do it.
i have tried lowering the TCC lock speed to less than the shift speed and also above it. tried it at various MPH settings, etc. D5074 on and off, adjusted ramp rate, minimum & maximum duty cycles, raised the slip inhibit to max and it behaves the same.
driving down the highway going 65 and just over 2000 rpms sucks, especially for MPG
any ideas on what to look for or change to raise the converters confidence?
if needed i can upload the tune
thanks Jason