Until this thread I didn’t know 6.7s had two cooling systems.
Turbocharger circuit isn't shown on these diagrams. Perhaps it is entirely oil cooled, but I doubt it. A couple typos in the first image...EGR vs engine.
Primary High Temperature: Engine water jacket and oil cooler...heater core
Secondary Mid and Low Temperature (two pass radiator): EGR cooler, Charge air cooler, Fuel Cooler, Trans cooler
yeah that solves the issue, get into new one every three years......solved, or more like kicking the can
Rather than change the fluids, change the whole truck. The key to keeping maintenance affordable on these trucks is to neglect them. As a recent used truck shopper, out of warranty and under maintained sure doesn't reflect in the asking price, NADA, blue book, etc.
I almost bought a local one owner 2016 powerstroke CCSB lariat. Clean as a whistle. Cleaned the underside anytime we got snow/salt. Not a single door ding or stone chip. Owned by a car guy. His pride and joy. Used it to commute, take kids to school, and tow a single car open trailer to the dragstrip. Never towed heavy. Front end was mostly tight. 170k miles. All original fluids. He had only recently done the CCV filter and it was leaking oil out of two injector seals, a CCV breather line, and the lower oil pan seal. Couldn't bring myself to buy it. Guy built 700 hp coyote mustangs but couldn't manage to go beyond air filters and oil changes on a 65k truck.
I bought a 2014 cummins despite primarily shopping 2015-2016 powerstrokes. Far less power and a miserably inferior transmission compared to the ford 6r140. In fact, all of the truck is inferior to a contemporary ford except the simplicity of the motor. One coolant system (two radiators in parallel), one thermostat. I want my deleted and tuned 320k mile 2006 duramax back.
and tries to beat book time to maximize his pay...and really don't give a darn about doing any job correct.
Book time and $150-$200 / hr shop rates are the reason these trucks are undermaintained and prohibitively expensive to own. On one hand, it can be hugely successful to open your own diesel mechanic / diesel performance shop and only work on pickups. On the other hand, it will eventually cause the death of the light duty diesel vehicle.