Clk430 Rev Limiter
Unlike in an engine, where oil always follows the same path, ATF doesn't always follow the same route. ATF typically flows from the pan through the filter, to the pump. Oil pumps are driven by the pump drive hub of the torque converter. This means when the torque converter cover is rotating, the oil pump is pumping. After the fluid leaves the pump, the flow of ATF is dictated by a part called the valve body. The first stop for the ATF in a valve body is the pressure regulator valve. A pressure regulator valve is one of the few parts I know of that exist in all automatic transmissions. However, sometimes that valve is physically separate from the valve body. At any rate, after leaving the regulator valve the fluid goes to one or more of the other valves in the valve body. The job of valve body is to regulate (hence the regulator valve) and direct fluid (the purpose of the other valves in a valve body).
The valve body, which is in charge of directing fluid, knows whether or not the transmission is in drive, or whether it's in neutral. It is entirely possible that parts which ordinarily receive "x" amount of ATF at 5 thousand RPM while in drive, only see a fraction of "x" amount of ATF while in neutral. If so, those parts which are supposed to be bathed in ATF may be severely damaged if they don't receive the correct amount of ATF.







