Yeah I never thought of that. I don't know a lot about trans but does going up a hill without the tc locked really build a lot of heat compared to accelerating normaling from a stop?

When its lock in OD the rpms are lower if it would unlock or downshift rpms would probably be about 500-800rpms more or something. This means the fuel injectors are injecting about 50-70%more of the time using more fuel. So if your engine can make more torque in lower rpms and not have to downshift it is more efficient?(the question mark is becuase im not stating this)


Since were talking about this when the tc is locked in overdrive why dosent it have some sord of overrun clutch or does it? So coasting down a hill the engine dosent hold it back?

And if DFCO helps so much I don't see any reason besides drivability why GM wouldnt have at least some. I hate the fealing that the engine is always trying to fight the brakes and goes 20 mph when ideling. Im guessing the benifit of milage isnt worth the driveabilty issues with DFCO, but then couldnt they have integrated it into the brakes? Ive heard the HD 6L90s trucks have a engine braking shifting(I guess theres no way to make a system like this on the older LS1 pcms?)