I dumped my ford gold about 2000 mi ago. I flushed with tap water, then flushed with 24 gal of distilled water to get back to a ph of 7. I decided not to flush with restore and restore plus because of the overwelming stories of clogged oil coolers after chemical flushes. I have a 24° delta, it did not go up or down after the flush/backflush. I did not notice alot of debris during the flush. Then I installed a bypass coolant filter. I ran the filter for right at 1000 mi. I've been running the truck on short trips, it is not a DD. Most of the time has been with the heater valve closed to maximize flow. The outlet hose has remained hot, so I suspected the filter was not clogged. I opened the filter and rinsed the filter element and housing in a coffee filter, to see what I got. The oasis shows an egr cooler replacement, but no oil cooler replacement, 170k currently. I'm happy, i'll be replacing the oil cooler after the new year, hopefully. My feelings are generally, if you or the PO, did not maintain the coolant, flushed with chemicals, or ran straight water for any length of time, you will have a tough time with oil coolers.
Tips: Release your system pressure before you close isolation valves.
Catch the coolant in a coffee filter, and dump it back in, I got a little over a cup.
Don't overtighten the filter, it's not necessary, just check for leaks.
Coolant is fine.
The debris just looks like flakes of mineral deposits i've seen in any coolant system, and maybe a little dirt.
Sent from my phone that somebody didn't help me get.