why is water rushing throuh my dash.i already have oil in radiator. i first heard the water when i turned on the heater..... i appriciate any comments or help.

OK, a little more info, what do you mean by "in the dash" ?

Coolant runs thru the heater core, but you shouldn't have oil in the rad, something's definetely wrong.

What engine do you have? there's a few possibilities.

first of all thanks for reply. got 22r-e engine over 170k mi. first noticed coolant lose bout a month ago when rpm would surge when at idle at a red light but truck never got to red line hot. after refill coolant it ran fine. 2days later i decided to check under hood & coolant low again & brown, also oil like lite chocolate milk shake. i did oil change & radiator flush, oil may have just a trace of coolant but now coolant looks like milkshake & when i take off & change gears i hear water flowing behind dash like its being poured from one cup to another. i wonder if it could be something besides head, or gasket?