I got my dad's 1999 f150 with a v6 with about 30k miles on it. While there is not mileage on the fluids, there is time. I'm going to change out coolant and make it fresh. How do you suggest I do this and how many gallons of antifreeze do I need.

Is the v6 in the 1999 f150 considered to be a good engine. Much rather have a v8 but it is what it is

 

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Capacity:

4.2L V6 engine with 1 row radiator 19.0L (20.1 quarts)
4.2L V6 engine with 2 row radiator 20.4L (21.6 quarts)

 

This may surprise you but the coolant capacity can be found in the owner's manual off all places. It is in the glove box in case you didn't know.

 

If you don't drain the block, it won't take that much.

 

That's why you use 100% antifreeze instead of 50/50. Using the flush and fill kit and draining the radiator, it will take just about half of the listed capacity, giving you a 50/50 mix when you are done.