It's time to drain and replace the coolant in my 99 F250 SD. The book tells me the capacities, but it doesn't say if this is straight coolant, or diluted with distilled water?

I know one of you experts out there can tell me?

Thanks in advance.

ldcattle

 

YES, you refill with a 50/50 mix of coolant and distilled water.

Good luck...

biz

_____________________________
2003 F250 SD SC 142" XLT FX4 V10 Auto 4x4 3.73s

 

Thanks...I knew it had to be diluted, I just wasn't sure how much. My 96 F350 PS book gives you step by step, but the 99 doesn't.

Thanks again.

 

Yes 50/50 mix with water, UNLESS you buy one of those premixes which already have water and for which you pay a lot for half water.

Most capacities show more than you are likely to be able put in. This is beacuse when you drain the system, you almost never get it all out. So... Take the capacity listed, and buy the anti freeze to make up 50%. Then when you add coolant, put the antifreeze first. This way you know you have the 50% antifreeze quantity which will mix with what water is left in the block.

Be sure to bleed the air and check coolant levels ever few days and top up as needed. The air bubbles will work their way out of the system over time which means you need to top up.

Later, whenever you top up, use antifreeze not water. this helps make sure you are replenishing the components of the antifreeze as some of them are "used up". Water just adds volume and dilutes you old antifreeze.


Distilled water is good. Soft city water is also usually OK. Hard city water is one of my last choices. There are arguments about Distilled, versus DeIonized, vs purified vs city water etc. Argument usually centers around the metal leaching characteristics of some extremely pure DI water. My company chemist said that as long as you have the proper antifreeze mix, the only questionable water is really hard water.
Good Luck,

Jim Henderson

 

Thanks Jim...

 

here is some good info on it: https://www.ford-trucks.com/forums/s...=coolant+flush