rjones
I think the main requirement for the Cummins is low silicate. Other than Fleetguard, none I looked at had anything on the label about silicates. I also wonder how people using 50/50 get all the old stuff out. I flushed mine according to the article in the last TDR issue and drained the radiator, then filled with Fleetguard concentrate and couldn't even get 3 gallons in. After topping off and filling overflow I'm about a quart short of 50/50 figuring a 6 gallon capacity. George