grrrrrrrr......
so the gold coolant is not a NOAT but a HOAT coolant... it is engineered to make a 'skin' over hard parts... it's a good concept that works in some applications like magic. it's a bad concept in an engine that utilizes a coolant sleeved EGR, as it is flashed to a redonkulous temperature and forces separation of compounds, and falling silicates.
ford tried to make the gold product cover too many vehicles- it was FORD, not NAVSTAR... Navstar's are sent to market with red NOAT coolant...
the combo of a coolant to oil cooler embedded in the valley and with a coolant sleeved EGR cooler was stupid....
now we're going to discuss casting sand whether you follow Bill's religion or not... it's true they were cast with what the industry calls sand... it is true not all of that sand was removed- it's impossible. but what actually happens is misunderstood... it's actually pretty simple- the 'skin' forms around the casting sand, increasing it's size, and joining others like it- until they can't fit through the passages of the oil cooler. hello clogged oil cooler...
then, folks improperly flush... they use vc9 and go straight for the scale... oops... but that should be explained first...
the skin on the hard parts isn't a bad thing... but it doesn't survive the heating cycles of the EGR coolers in a stock DPF truck during the regen cycles especially, where they can maintain as high as 1500* for a good while. flash boil, chemical alterations to the coolant. little bubbles slapping metal at hyper-sonic speeds, and damaging them... breaking the skin... cutting through metal like sandblasting... cavitation... front covers leak, ultimately... impellers get chewed to ineffectively moving coolant... chunks of 'skin' break free and clog oil coolers.... scale forms on now unprotected metals, especially when it becomes a conductor over differing metals and attacks the weaker ones... not good... the interesting thing as related to maintenance, though, is the formation of scale due to the effect of conductivity of metals and it being spread throughout the cooling system, and then using a product that attacks the scale as a remedy- it's BAD juju.
restore is a product available at cummins dealers. if used properly it attacks the skin, and melts it. you gotta follow the letter of the instructions and use proper concentration an achieve the proper activation temperature for the prescribed amount of time... then you gotta flush several times with water alone.... not once, twice, or three times, but several more than that... then, when the 'skin' is gone, THEN you attack the scale by using vc9 (motorcraft product) OR Restore Plus... it attacks the now fully exposed scale... same thing... proper concentration proper temperature proper time.... then you flush the several more times again.. block plugs out type flushing... a lot....
at this point, the pretty much harmless 'casting sand' is mostly gone, and all of the 'skin' should be gone that was adhered to them... it is safe to introduce distilled water to the tune of 20 gallons or so as you continue to flush, and then top it with coolant... but why in the hades would you reintroduce gold? use the freakin RED NOAT, and the better is the CAT EC-1 ELC... you're concerns about your cooling system will be like the tin can you just booted half a million miles down the road in front of you, instead of test strips and flushes every 30~50k miles...
a coolant filter is not required... not at all... AFTER you PROPERLY flush and remove gold... but... you can introduce one for less than $30 by piecing it together, tapping the heater core lines, and trap anything larger than 25uc or so, and guarantee the issues surrounding the coolant to oil cooler won't ever touch you.. that is relatively cheap insurance, especially considering replacing an OE oil cooler ($350 or so for the part) won't set you back $3k+ down the road...
and. for what it's worth... ELC NOAT RED coolant doesn't have the issues with heat cycles like the HOAT gold... Ford screwed up. it's easy to fix, though... we have the technology...
