I have a 2010 F250 with the 6.8L V-10 that just turned 50K miles. I just recently purchased it and I am the 2nd owner and pretty sure it has the original coolant in it. I am going to replace the coolant. I bought 4 gallons of the VC7-B coolant. My plan is to just drain the coolant, refill with distilled water, run it a little bit drain, repeat, then drain and refill with the proper amount of coolant, and top off with distilled water. Is it necessary to run a chemical flush with only 50K miles even though it's 12 years old? Thanks,

 

I'd run some of the Prestone cooling system flush chemical through it along with your distilled water refill/drain/flush.

You might also test the existing coolant for its pH level---always interesting to know how well its held up over those years. At just 50K miles though it should test very well even now.

 

I thought about that, but I was just wondering if it would hurt anything if i didn't get all the prestone super flush out,

 

I did the empty and refill with water three times before adding as much new coolant as would fit in the system. I also drove about 100 miles with fresh water in the system to completely clean anything left behind---only then did I add the new coolant.

I'm fairly sure Prestone et al wouldn't add something detrimental to the cooling system if some bits of it remain behind and mix with new coolant. Do keep in mind the Modular Motors, both V8 & V10 hold a lot more water/coolant than we expect. I'm told the V8's have up to 8 gallons total when properly filled.

 

Ok thanks for the reply, I will use the super flush, just happen to have some that I was going to use on my Expedition and ended up getting it done at the dealership instead while they were doing some other work. I think the owner manual list the coolant capacity at over 28 qts so 4 gallons of undiluted antifreeze should cover it. Thanks again.