97 4rnr 6 cylinder reservoir cap popped off & antifreeze is light brown when it overheated, no white smoke from exhaust no antifreeze in oil, could it be trans. oil in radiator, & what would cause this? also trans. started shifting funny, its an automatic ..thanks for any help, Pete

 

Check the transmission dipstick, see if anything looks funny thee. Usually when the trans cooler links they call it the 'pink milkshake' - because the red ATF mixes with the coolant. It's possible you had burnt looking brownish fluid? This happens because there is a transmission cooler/warmer (when the trans is cold) built into the lower tank of the radiator. This can crack over time, one of the few problem areas on a 3rd gen, and it usually makes a mess in the engine and can ruin a trans in fairly short order.

You might also try soaking a white paper towel in the coolant, see what the oil looks like when it soaks in.

 

Paper towel was dark brown & was low on fluid, so basically a new radiator, antifreeze, 7 transmission filter & oil change should get me up & going again?....Jomoka

 

New fluids first for both systems and trans filter. Unless rad is confirmed with leaks, I wouldn't replace it yet. May need to check your hoses, water pump, cooling system for leaks. If coolant level is still low, may be a tiny head gasket leak without the white smoke, perhaps?

If oily presence in the rad, then yes, another indication to change radiator.