The Legend of the Missing Coolant

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New Member
May 7, 2019
Truck Year
This is an ongoing story about my clueless dealer. As fellow RAM enthusiasts/masochists, I imagine you all will find it entertaining.

In December, my 2015 RAM 1500 threw a "Crankcase Breather" code, I believe it was P04DB. I took it to the local (~2 miles) RAM dealer and they replaced it. (Apparently the breather is considered a wear part and not covered under warranty. Whatever...)

On May 29th, I brought my truck to the same RAM dealer to diagnose a leaking coolant issue. My truck leaks about a quart of coolant INTERNALLY a month (even if its not being driven) so I took it to my dealer thinking it was the EGR cooler. In addition to this, the P04DB code came back. I only use it to pull trailers, so it doesn't get used as my daily driver. It had been sitting for ~2 months before I started it, and I was alerted to this issue when a mixture of coolant and oil popped off the oil cap and sprayed the underside of my hood. Drivability and engine noise etc was not affected (as far as I can tell). I also need the AEM update for the settlement, so I figured they could do this in one trip. I lay this all out for the service writer and ask to see what he's writing to the mechanic. It looked good.

On June 7th, the dealership called me to say the cause of the problem was during an oil change (of which, THEY performed) the tech simply forgot to replace the oil cap, causing the spillage and there's no coolant leak and I can pick it up at any time. Wut?

I called and BEGGED the service writer to do an oil analysis. He stated since there's no coolant leak under the truck, no coolant could be in the oil. Double wut?

I asked him to please take the valve cover off and check for coolant if he won't do an oil analysis yet. He said he would.

On June 13th, the dealer called me again and said since the oil isn't milky, no coolant could mix. I ask him if there's no coolant under the truck, where could it go? He advised me that the coolant system may eject coolant when under extreme load. I asked him if sitting in a driveway, not started for 2 months is extreme load. He denied this, but stated that coolant leaking at that rate is a normal operating condition.

At this point, I requested an oil analysis from the dealer and I am doing my own independent oil analysis. I also called FCA and they didn't give me much resistance before assigning me a case number.

This story is still ongoing and I will keep you guys in the loop in the hopes that my experience could help others.


cs in Alabama

Active Member
Feb 21, 2019
Truck Year
"My truck leaks about a quart of coolant INTERNALLY a month"

(dealer says) "coolant leaking at that rate is a normal operating condition"

Ha ha! I think the EGR cooler is leaking too. Remove the EGR diffuser tube and see if it is all sticky / sloppy. If it is, use a flashlight to look into the intake and see how bad it is in there as well. The coolant can destroy the intake and the intake valves. It covers the swirl valves and ruins the intake. Demand a new intake and an engine inspection with photos at that point.

Eco diesels that become diesel / steam hybrids have lots of problems and don't live long.