About a month ago(maybe a little more) I topped of my radiator and overflow with green coolant. It had orange coolant in it and I didn't even notice. Yesterday on my way home I noticed my temp gauge got just above halfway, put on the heat and it went back down. Same thing today. Have I royally messed up my system by blending? I appreciate any input. Not wanting to spend $105 on a system flush.

 

Get some proper coolant. My favorite is peak global lifetime from Napa mixed with distiller water.

No need to "flush". Just drain radiator and block drain. Fill with distilled water, run for a minute, drain back out. Fill up with the right stuff.

 

So, no need to worry about the coolant already in the engine just the radiator? If that is the case, I feel very relieved. Thought I had turned my coolant to gel.

 

You need to drain all the coolant, radiator and engine block. No telling what mixing coolant chemistries will do.

 

You need to drain all the coolant out. It is not recommended to mix the red and green coolant. I have heard pros and cons on the red coolant so not real sure about it. The green has worked for years for me so I tend to stay with it. I am sure my 01 runner has red in it and no problems with it.

 

Wait, was the coolant really orange? If that truck had dexcool in it you're gonna have a bad time.

 

It was "universal orange" and I added "universal green." I didn't add much probably in the ounces. Thinking I'll flush the radiator, run it a bit and flush it again.

 

So, who put the orange coolant in? Just because it's orange doesn't mean it isn't chemically compatible. Seems I recall having used an orange coolant some time ago without issue. I use Prestone low-tox anymore, though.

Some internet reading may alleviate your concerns...
http://www.aa1car.com/library/2004/us120426.htm