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Low coolant warning this morning

6K views 20 replies 10 participants last post by  Pappyt2 
#1 ·
Truck was fine Saturday ,it sat over rest of weekend and this morning I decided to drive it too work and low coolant message came on twice in 1st mile. I dismissed it and this afternoon it ran fine I remote started it and when got to it and put key in there was no warnings. I wondered if it was just cause of it being 20 this morning and this has been the first time driving it this cold ? Checked tank when I got home and it was at the full level I hope it’s ok. I haven’t had block heater recall done yet mainly because I didn’t want them to mess up something doing that. It’s just way my luck goes
 
#3 ·
got no idea what to say because we got no idea what you have, fill out yoru signature......................
 
#4 · (Edited)
Full to the line when the coolant is warm means it's low when the coolant is cold. The tank level indicators are for cold coolant -- since it needs to be cool/cold when the cap is removed....

Add enough to be at least at the the full line when it is cold.


Don't forget that the cap on L5P is left hand thread!
 
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#5 ·
#6 ·
#9 ·
Got my sig filled out. Don’t know why it doesn’t show up. But truck is 17 Duramax
 
#13 ·
Anyway I figured it was just cold weather thing. I haven’t checked since. I will tomorrow check level.
 
#16 ·
Its the sensor, they have to replace the surge tank. Just had mine replaced on my 2017 had about 81,000 miles on. Not a covered under warranty. I would get the same thing for a bit and then it would go away for a while and then pop back up. It is happening to a lot of them the parts were on back order for all most a month.
 
#17 ·
Well, my '18 started giving me the low coolant warning a couple weeks ago. It had about 49K miles on it. I took it into the dealer. Previously it was serviced to address the related TB. The mechanic found a small leak out of the water pump's weep hole. They replaced the pump. I got the truck back this past Monday. Since I have had the low coolant warning twice. The first time, it took 3 pints to fill it to the mark when it was cold. I got the warning again today and it took another pint +. The level did appear low both times and both times it was cold. So, I am not convinced my problem is the sensor. It could be that they did not get all the air out of the system when they changed the pump. But my '08 max never gave me any issues with over 250K miles on it. Kind of disappointed in the LP5. One more low coolant warning and its back to the dealer.
 
#20 ·
That’s good to hear. But I still haven’t driven truck since that day. Today the weather is sucky but I’m gonna look at it Saturday if I can
 
#21 ·
Went out yesterday and check level. It was fine. Started it up and let her run few mins and message didn’t come back so maybe it was a fluke
 
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