QuestionI have a Chevy 400 small block mated to a turbo 400 transmission. After the engine warms up to about 190°F and in idol, the transmission leaks fluid out of the top of the dipstick, which is about valve cover high. Even driving the truck, the fluid leaks out of the dipstick. The leak is pretty excessive, approximately a quart in 10 minutes.
Do you have any ideas as to what would cause this.
Regards
Tolby McGlothlin
AnswerI can think of two things.
The first and most likely is that your vent on the top of the transmission case is plugged with crud.
The second is that there is some contamination in the transmission fluid the has lowered the boiling point of the fluid from 300 degrees down to 200 or so, this is making the fluid boil up and overflow from the increased pressure in the trans. You can spot this by inspecting the fluid. If it looks nice and clear, and red, and doesn't smell burnt or show any milky look, then it's probably a plugged vent.
Dick
