automatic gearbox stalles engine

hello,

since the new update i'm redoing my Semi engine and gearbox mod,

i added new gearboxes to the semi some manual and some automatic, the manual gearboxes do work fine, but the automatic gearboxes do let the engine stall as soon i select D or R, as long as i hit the trottle just before i put it in D it hips and the rpm goes down a lot and almost hits stalling but than it goes, as soon as i brake and stop it stalles too


how can i adjust the moment of when the clutch(torqconverter) brings over the power so it wont stall