Very true indeed.If you see inside the Transmission belly to where the oil pick up is located in the sump you'd see why.The Trans in an enormous hydraulic pump sucking horse power from the engine & needs oil under extreme pressure to provide drive.Transmissions are very sensitive to oil level, viscosities & heat stress.Sorry if I sound like a Scientist or a trans Greeny.ATF has a high boiling point & still remain quite viscous, but will still boil.The poor tranny often runs warmer than the engine, being at the rear, generating it's own heat & absorbing heat from the cylinder block.I've dun trans services here in my drive & filled up both our cars to where it should be & often as I drive down our drive(being on a slope)the trans will seem to drop into neutral meaning not enuf fluid.I also run huge V8 trans coolers on both our cars which is an excellent investment into trans life extension.Even if you don't tow, the extra fluid capacity & the cooler being situated in front of the air condenser does wonders & keeps the engine cooler also,..bonus..!!Often in summer periods the lame factory radiator trans coolers are ineffective & you fry the oil.Around $80 gets a good V8 tranny cooler, half an hour to fit it if you have the rite pipe spanners.I run a V8 cooler on her EFI Berlina 6 & neva had a drama.
P.S. I run small V8 fuel type filters on my trans & power steering lines.It prevents gall stones.
