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Discussion Starter · #1 ·
Last December I had the coolant system flushed at the dealership and ever since I have noticed the coolant level in the expansion side of the tank getting lower and lower both when the coolant is fully cool and if it is at operating temperature. Another question is the dex cool is not a bright orange color like I am used to seeing, it seems to be a darker color orange especially when at operating temp.
 

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Last December I had the coolant system flushed at the dealership and ever since I have noticed the coolant level in the expansion side of the tank getting lower and lower both when the coolant is fully cool and if it is at operating temperature. Another question is the dex cool is not a bright orange color like I am used to seeing, it seems to be a darker color orange especially when at operating temp.
if you get the truck to operating temperature, park it, then come back the next day, is the upper radiator hose hard still? Without more information, just based on what you said my guess would be a head gasket failure. Exhaust gas would discolor the fluid while also pushing it out the overflow so the level would go down and the color would darken.
 

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Discussion Starter · #3 ·
Upper hose soft after sitting. No signs of any coolant being pushed out the overflow either. The coolant was this color when I got it back from the flush. They also tested for head gasket failure when I had it in back in March for a steering gear replacement and said everything checked out.
 

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Upper hose soft after sitting. No signs of any coolant being pushed out the overflow either. The coolant was this color when I got it back from the flush. They also tested for head gasket failure when I had it in back in March for a steering gear replacement and said everything checked out.
any weeping around the water pump? if your not blowing the coolant out the over flow, your either leaking it somewhere or burning it in the engine. Do you have an intact EGR? the cooler can fail and allow coolant into the engine. You would see white smoke with this though and the inside of the EGR would appear steam cleaned. not sure about the coolant color, maybe they used a generic brand or maybe there was some contamination at some point in the flush with the green stuff. That will give it a darker brown orange tint.
 

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Discussion Starter · #6 ·
Yes as of right now EGR is intact and have never had white smoke. Is it possible the system has just been slowly pushing air out that was trapped since the flush? The pressure side was not completely full to the top when I got it back and the last of the air space is gone in the pressure side as of about a month ago. Maybe I am just overthinking this.
 

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Yes as of right now EGR is intact and have never had white smoke. Is it possible the system has just been slowly pushing air out that was trapped since the flush? The pressure side was not completely full to the top when I got it back and the last of the air space is gone in the pressure side as of about a month ago. Maybe I am just overthinking this.
i would like to think that the dealer would have properly bled the system, but you never know. If you dont have smoke, dont have excessive pressure in the tank, radiator hose isnt hard and you see no other signs of coolant ingestion in the engine or of a head gasket failure then it would likely be safe to drive for a few days and see if the level stabilizes. That said, it should only take a couple heat cycles to purge all the trapped air. One other thing that might be a contributing factor is the overflow cap, if it is failing you might be boiling off water and condensing the coolant. it needs to hold 15-20 PSI in order to elevate the boiling point of the coolant above engine temps. You could test this with a pressure gauge, or you can throw a 9$ part at it and see if that fixes it. My cap on my 15 was bad when i bought it, had to replace it.
 

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Discussion Starter · #8 ·
Yea I replaced the cap about a year ago but thinking it may not be good. I also don’t trust many dealerships anymore Because of past experiences where they were supposed to replace something and they said they did under warranty and come to find out a year or so later they didn’t. I do all the work myself on my truck and am very knowledgeable but when it comes to cooling systems there are so many different pieces on these diesels it stumps me.
 

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Yea I replaced the cap about a year ago but thinking it may not be good. I also don’t trust many dealerships anymore Because of past experiences where they were supposed to replace something and they said they did under warranty and come to find out a year or so later they didn’t. I do all the work myself on my truck and am very knowledgeable but when it comes to cooling systems there are so many different pieces on these diesels it stumps me.
im guessing you dont have any wet spots on the ground or under the truck from where there could be a leak?

Since your dealer sounds about as incompetent as mine, you may want to check the lower radiator hose by the passenger tire to make sure they put the C clip back in and the hose isnt loose and dripping, though id expect that to be a very large leak if they had left it off. That should be the only hose they disconnected do drain and flush though.

For future reference by the way, changing coolant on the LML is pretty easy, pull the C clip off the hose connection, pop the hose off, make a huge mess, reconnect the hose and fill with water, run the engine up to temp, pull the hose again, make a bigger hotter mess, then reconnect, and fill with coolant and water. Run the engine up to temp to purge the air. Make sure the heats on so you circulate the heater core too.
 

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Discussion Starter · #10 ·
Yea nothing, no leaks anywhere and I have Checked every place possible.

Thank you for the info, I may just flush it myself.
 
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