So i noticed this happened once in a drivethru with a slight hill as i put it in drive noticed car rolled back a little kinda like how a manual trans does, was like this is weird.So i had my buddy/mech check it out after he did a 3x3 trans refill and he checked it on very steep hills and sure enough it rolls back alot on steep hills and only stops when he gives it gas.And im sure this is not normal as i dont recall any other of my cars doing this it can be a safety issue also.My buddy wasnt sure what it was but thinks it has something to do with the gear ratios on the TC.Has anybody else experienced this??

 

An automatic slushbox with a torque converter isolates the engine & transmission from the drivetrain. When you are idling, the engine and transmission are spinning one side of the TC while the drivetrain side is stopped. If the wheels roll backwards, that just makes the drivetrain side spin a little in the opposite direction. To the TC, it would be the same as giving it a little gas with the brakes firmly applied.

I dont see how this is an issue, but I'd like to hear other's take on it. I think it's just the nature of the low, low-end torque and the TC design.

 

When my wife gets back I may try to replicate what you are talking about. See if mine does the same thing.

 

i noticed this yesterday actually, on a steep hill in providence RI at a redlight. foot on brake and when i when to go switch to drive there enough of a roll back to where i took notice...

 

With cold tranny fluid, mine will happily sit on the drive in reverse. If it is warm, it tries to head-butt the garage door.