i understand that an automatic transmission delivers power from engine to wheels using a torque converter which, acts like two fans. one blowing fluid into the second one to make it spin. Also if a tranny is equipped with overdrive the torque converter locks. If that is true than in lower gears is there slip between two "fans"?

is this slip significant power loss wise?


thanx

 

Good guestion newbie - Yes the torque converter works basically just how you explained it. In our cars the touque converter locks up (like a manuals clutch) only when the car is in 4th gear, crusing above 30 MPH and with the transmission oil at operating temp. It will not lock up when the engine and trans are cold.

As far as power loss goes, yes there is some power loss in the converter. When it's locked that power loss is basically eliminated.