Black or light brown; medium consistency.
Oil dripping on the driveway or leaking onto the engine (often accompanied by a “burning” smell) can signal a leaking valve cover or oil pan gasket.
Coolant colors vary. Traditional coolant is yellow or yellowish green. Extended-life coolant is an orange/amber color. Both types feel slick and slippery to the touch.
Coolant on the driveway can signal a leaking thermostat gasket (unless it is an obvious radiator leak). Leaks around the thermostat are easy to spot.
More difficult to detect is an intake manifold leak. Coolant (and occasionally oil) may be visible where the intake meets the cylinder head, or on the dipstick when checking the oil. White smoke may come from the tailpipe.
Oily and dark red; thin consistency. When a transmission pan gasket leaks, fluid is almost always on the driveway or on the garage floor. It may also be visible around the seal edges. One quick look under your car may reveal dripping fluid around the transmission pan.
NOTE: To get a true indication of a leaking fluid’s color, catch a drop of it on a sheet of aluminum foil.