One trick we always use is to paint the coolant side of the freeze plug with Permatex Gasket Sealer, the old tar like Permatex, to resist rusting out.

I got the report back from Empire Caterpillar today. The said coolant was cloudy & Nitrate level was low. Also, here's some specs

BP (boil point) 104
FP (freeze point) -31
GL (glycol) 36
PH 8.6
CON (conductivity) 1103

I talked to the lab tech & they recommended flushing everything with clear distilled water or conditioned water which was mentioned here. He was recommending ELC coolant but said there was no reason the green shouldn't be fine. I will also use conditioned or distilled water. I'm also going back to see if my grounds are actually ground. Brass plugs this time. Quanta is out of paint so I'm on hold for that now...UGH. Always something

Any other thoughts? I'll start on it on Monday....thank you, Joe

The 8.6 PH level isn't bad. If below 7 that's when corrosion becomes a problem. Assuming the lab result temperatures shown for FP and BP are in celcius and those seem to be in the normal range.

Here's the latest on coolant. We got some coolant test strips from the parts house & conducted some different test. they test Nitrite, PH, & FP. These verified what some had already mentioned. We did 3 tests with coolant that had been sitting in my truck for about 4 hours. Coolant was at 95 degrees

Test 1 was the coolant that I sent to Caterpillar. The results were vere close to what Cat said.

Test 2 was a 50/50 mix using new green antifreeze & water from the city. The results were barely better than what Cat tested

Test 3 was a 50/50 mix using new green antifreeze & deionized water from our system on the house. All results were substantially improved.

I guess I should've done one with distilled water. Maybe this week I'll do that....Joe

I’ve been reluctant to tell this but it has worked in my engine I had done in 2005. The engine builder told me before I run my engine to go to the auto parts and get one tube of the old time silver radiator stop leak stuff that’s been around for many years and put it in the radiator. He said it worked to help seal the freeze plugs and they would not give me any trouble.
His name is Sherman Gerlach, I always listened to him. I sure miss my friend.

When I worked for Napa many years ago we sold lots of Alumaseal....Joe

When I was more active with installing new engines, years ago, I would do this too, BUT, I always bypassed the heater core until the coolant ran clear of silver sparkles. I HATE replacing plugged heater cores.

Just an FYI, US Tool & Mfg. Co makes most core plugs in stainless. The ones I have used have no writing on them. They are out of Addison Ill.

Also, I have always used Permatex sleeve retainer 64040 or Loctite equivalent 620 for core plug installation.

A good company,I drive by them almost every week.. https://www.ustoolandmfg.com/