Probably a dumb question, but I just picked up a 2018 with the 3.5 ecoboost and will eb changing all of the fluids.
My question is I have watched many videos of coolant flush or change, and I see online there are concentrated and prediluted forms of the newer yellow coolant, does it matter which I use? Can I use the concentrated only or do I have to add water with it.

 

If you use the concentrated coolant you must mix it with distilled water. Pure coolant does not protect from freezing or overheating as well as a blend. See the chart below.

You need to do a lot more research on this before you attempt to change out your coolant. There are lots of threads in the forum here on this topic.

 

Well I have been doing research, and any video I see about the difference in yellow and orange fills with concentrated, which is why I asked

 

maybe you are not familiar as to why its concentrated? Coolant is typically mixed 50/50 to suit ALL climates... however some climates can benefit from less glycol and some can benefit from more.
Coolant chemical companies decided the end user is too dumb to understand so they have "ready to use" versions for people not well versed in car maintenance. Also they put it at a cheaper price point because dolts will pay more for less.
But this question is definitely right up the alley of your local parts store counter flunky. Remember retail people are not just selling you product they are also professional experts...lol

 

If you live in a really cold climate you usually fill with concentate. A coolant drain rarely completely empties the system and there is no way to precisely tell how much coolant and at what concentration is left in the system. That could over-dilute the coolant for those really cold climates. For my location, I like to try and achieve a 60/40 coolant/water mix. After running the truck I can pull some coolant out of the top tank if needed and adjust the final concentration by adding either concentrated coolant or distilled water depending on need.

If you are going to replace your coolant, pay attention to several points:

1. Check the condition of all your hoses. Better to replace any in question now than later after you've lost all that new coolant on the side of the road with a hose failure.
2. Replace the thermostat with a new latest revision Ford/Motorcraft unit. For some reason the factory thermostats don't like coolant changes and often won't fully open leading to overheating issues. Aftermarket thermostats just don't work well in these F150s.
3. Use a vacuuum filler if at all possible. Getting all the air out of the system is key to a properly functioning coolant system. Burbing to get the air out is often not that reliable.
4. Dispose of the old coolant properly. It is hazardous.

 

In Mississippi, you need to use a 50/50 mix of coolant concentrate and distilled/soft water. A higher concentration of coolant protects against freezing to lower temperatures, but is less efficient at cooling, which is your primary concern in the southern U.S. The concentrate is more economical; the pre-diluted stuff is for topping off. You can get a simple tester at auto parts stores to check the mixture. If you haven't changed coolant before, and aren't confident you can achieve the correct concentration and get all the air out of the system, you might consider having a shop do it this time.

 

Getting to the concentration you need is the difficulty. On my ‘18 5.0 coolant change, I flushed several times with distilled water. The engine block held most of the water. Draining via radiator didn’t remove a quantity that allowed enough concentrated to get 50%. I was changing my water pump as well as T stat and Y pipe. That gushed enough. It took several refills with the second gallon ( on the 5, it takes 2 gallons) to purge the heater. Maybe someone with a 3.5 could chime in, but it wasn’t simple like old vehicles. Think about a shop doing it.

 

If you are asking about the difference between the older orange coolant vs new yellow, you can add the new yellow to the orange stuff. Probably won't find the orange juice as its been replaced.
I would personally get the premixed yellow motorcraft and eliminate the mix question.

And also, you can get the vac fill tool for under $100, and I highly recommend it.

 

Ford will charge you $240 for a flush and refill with the yellow coolant. I took my F150 to them because at the time, I didn't have the vacuum system. I now have the OEM Tools #27066, it had better reviews than the other one they sell. When you get the tool, be sure and inspect it to insure everything is there, and it is new. Amazon has a habit of sending out used items that have been returned to them.

 

Why is this one better than all the others? Most are half the cost of this kit price!