So I just picked up an 05 f250 in really great shape with 200k on it. I was doing some work on the truck and drained a couple gallons of coolant.
Coolant looks yellow. I'm guessing this it the Ford Gold. Although I don't know if any of the ELC coolants are yellow/gold as well?

I don't know the history of the truck, I decided to weld up the EGR cooler as a preventative, when I pulled the cooler it looks practically brand new. The coolant that came out of the radiator was very clean. The degas bottle is very clean. Everything is very clean. My oil/coolant deltas never exceed 8 degrees difference. Basically everything is working as it should.

I would like to swap from what is presumably the ford gold to an ELC, but since everything is working well I don't want to break stuff up and send it through my oil cooler. So in the case of a nice clean, working system what's recommended? Should I do a gentle flush with just distilled water and then go with an ELC. Should I add 50/50 ford gold back in? (again i don't even know for sure that's what's in there) Should I try to do a thorough chemical flush to remove all the silicates? I just don't want to create a problem.

 

IMO just get it to straight distilled water, then add the ELC.

 

Thanks, I was leaning this direction as well.

 

Rotella has a yellow ELC.
Looks like recycled beer as far as the color goes.

 

Agree. It will take about this much (app. 20-30). Make sure you buy distilled water & NOT water with minerals added. I'd pull the block drains too or at least the drivers side.

 

This is what I plan to do as well. Someone used what I think is Dexcool (orange color) in mine. Delta is ok so just going to do 3-4 flushes with distilled water. I plan to drain the coolant, pull the thermostat, add water, start the truck, throw the high idle switch and walk away for 30 minutes (well do some other work on the truck). Drain and repeat 2-3 more times.

 

Do the first 2 or 3 flushes with a garden hose and t-stat removed. Will make the process much quicker and cheaper. Then go to the distilled.

 

That is the process I used this last time.
Both block drains out and the petcock open.


Watch how SrMasterTech does this.

 

I've watch his video before and I may end up doing that. I still worry the quality of my well water might introduce other issues but I have recently replaced my water softener with one that specifically addresses some of the iron issues I have. A recent water test showed my iron levels were at a decent level now.

Either way I will probably skip using VC-9.

 

You can always use extra distilled water after the hose part.
I think I used 30 gallons after I was getting a clean return
with the hose. That and I also use the compressor to blow out
the heater core each time I opened the system to drain.

 

My well water is pretty hard. It has a fair bit of calcium, not sure what else. It looks clear, but those calcium deposits really come out if I were to boil it.

I can see the advantage of the water hose being able to get a good flush of the system, but I think whether going from well water to distilled or 50/50 antifreeze to distilled it would require the same amount of distilled flushes to get near 100% distilled.

I ordered a couple Fumoto valves to make the process easier.

 

Ed and I had a good chat about this topic. The 30 gallons + the extra after for
make water worked out to about 36 gallons. But the point he was making is
by the time you have pushed 5 6 gallon flushed through the engine the well water
concentration will be so far down that it will have no effect. BTW I am also on well
water and have enough minerals that if I don't dry the glass and paint I have very
hard to remove spots of white minerals marks. Also the math that Ed used did not
include the fact that I was blowing the heater core out each time. It did have both
of the block drains out but not the blow out of the heater core. So do that and
you should be ok.

One thing about the hose is you filling as you dump from both block drains and
the petcock with the engine running and that alone will kick things loose and allow
the water draining out of carry away anything that was knocked loose and that is a
good thing. Now if you also blow out the heater core each time and remove both
drain plugs along with doing this 5 times I don't think your going to find much is
left in the last distilled flush.