Is it enough to just flush out the radiator or should I do a complete radiator/engine coolant flush on a 2005 F250 with 180k miles. Also, what to use, regular antifreeze, 50/50 anti freeze or concentrated antifreeze. I read about all different ways. Which is the best way.

 

Welcome to FTE. A complete flush is the way to go using distilled water. If you do it yourself, you'll have a hard time getting all the distilled water out, so I'd go with the concentrate where you can check the concentration and adjust later.

The 2005 didn't come with a 7.3 diesel unless you bought it with the steering wheel on the wrong side Your profile says you're in Florida. Are you sure you don't have a 6.0? Don't buy the green coolant for a 6.0.

 

Thats what happens when you try to type too fast. Sorry, my truck is a 2002. Good catch, thank you.

 

Check this out
https://www.ford-trucks.com/forums/9...=coolant+flush

 

Yup, the link above is great. I found Zerex G05 to be the best priced coolant that meets specs. A little hard to find, Carquest had it here.