Hello,
I just replaced the radiator hoses, thermostat, and coolant on my 2012 Ford E350 5.4L with 185,000 miles. I don't think that this has ever been serviced before, so I thought I should flush the coolant and replace these parts as preventative maintenance. The manual said this engine uses a little over 7 gallons of coolant, but I was only able to get 3.5 gal (including the reservoir). I figure there must be a whole bunch in the engine itself or the heater core that didn't drain. I'm wondering if I should run the engine for a while, let the coolant mix, and drain out three more gallons and replace, or am I good until the next service interval?
I would have flushed the system with water using a hose a few times. Then drive around. Dump it out, and repeat until it runs clear.
Then fill the system with concentrated antifreeze. Since 3.5 is exactly half of 7, you will end up with exactly 50/50 mix.
I've done the hose trick when I was confident that I had most of the coolant out of the system. I don't really want to blow a bunch of water through the system when I don't have a way to collect that much coolant/water. As it was, I had a few big spills when unhooking hoses and probably lost a half gallon of coolant down the driveway. If I can get the rest of the coolant out another way, I'll try flushing with the hose and using concentrate to refill the system.
I think you mean quarts, not gallons. Only a steam locomotive would use 7 gallons of coolant. I usually remove the thermostat, set the heater on high and use low pressure (12 psi) air to blow all the water out of the system after a flush. Then refill with manufacturer spec. coolant and properly burp the air out of the system using a special burp funnel. Most cooling systems use approximately 2 gallons of coolant, in my experience.
I'll have to remember that for next time, as for the capacity of this vehicle, I just double checked the specs it calls for 28.8qts of Motercraft gold coolant which comes out to 7.2 gallons. I have a coolant burp funnel, but for this vehicle it wasn't needed. The only place you can add coolant is the reservoir and it's at a high point next to the firewall.
You're right - 28.7 quarts. Holy Moly Rocky!