Coolant flush and refill, latest info

[woodylmiller]

Getting ready to flush and replace coolant.  Was looking for a guide on the type of coolant to use.  ISM500 engine, looking for what is the best coolant these days.  What is the latest trend in coolants?  Thanks,

Woody Miller

09 Dynasty Regal IV

[vito.a]

I used Cummins Compleat OAT. 

Link to detailed thread:

https://www.irv2.com/forums/f123/changing-green-sca-coolant-for-new-cummins-compleat-oat-389479.html

I later needed a few gallons after changing a hose and used Peak OAT from Walmart.  

[jacwjames]

Road debris took out may radiator in 2015, I had Cummins of Knoxville do the repair.  Luckily it was covered by insurance. 

I talked to the shop manager about coolants and he recommended the ES Compleat which is also a long life coolant (listed as Life of Engine 1,000,000 coolant).  I didn't argue with him and that is what they installed.  If you read the fine print of all Cummins coolant it says you still have to check the level of inhibitors & PH.