Water or coolant?

should i be putting water or coolant in my sr5's radiator? a friend told me to put water but its starting to look rusty inside :/

coolant has rust inhibitors. you can also get a zinc anode to help with corrosion.

If its track only, and or, you flush it very frequently you can use water. BUT only use distilled water!! Even when mixing a 50/50 coolant mix, always always always use distilled water

If the passages look rusty you can drain the block of coolant via the drain plug by the oil filter, then hook up an author and blow the crap out once it's somewhat dry.

when i first got my car it had water in it. and it was bad. really rusty. it kept overheating and the heater would not work. i used white vinegar to flush the rad. fill it up, run it till it get to normal temp with heater on, let cool and drain via the bottom rad hose, for an extra flush after that, with the bottom hose off, put a water hose in it, remove the top hose turn on water and run the engine for a few min. flush the rad both ways. works real good. no more overheating, heater works like it is new. this place needs a like button lol.

Im in AZ and rarely do i need to worry about freezing. However, I still use 1/2 gallon of premixed 50/50, one bottle of water wetter and then fill it with water. I also pressure wash the radiator fins. I never have rust issues or over heating. When im racing though, i leave the heater on the first fan setting. This helps between runs.

i have a aluminum rad now. no problems at all after that.