2020 LM2...Where is the coolant going?

[Whipped500]

Have a 2020 LM2 Duramax with 14,600 miles. Since day one I've smelled antifreeze but reading on here, everyone seems to say it is nothing to worry about.  Well I am sure it is losing it now. When cool, it is about 1/2" below where it should be on the coolant bottle...where is it going? It's dry underneath. Motor is dry and no drips/puddles.

 

I've seen a few threads talking about this but never a resolution.  I am concerned about this and want to get it fixed because if it is burning it, I'm sure it isn't good for the DPF! I also think that by the time it does something very harmful to the DPF, it would be out of warranty.

 

I am going to make an appointment at the dealer, it's just that I don't have a lot of confidence in dealer mechanics lately,  especially if the scanner doesn't have a code to tell them to replace something. 

 

Just wondering if anyone has had this and have gotten fixed so I can have something to push back with if they say they can't find anything and just fill it to send me on my and tell me to keep an eye on it.

[reeseb]

Coolant expands when hot. That may be what is causing the difference in level.

Edited March 7, 2022 by reeseb

[Whipped500]

I've been keeping an eye on it since new. It was at the correct level when new, but now it is low.

[redwngr]

1 hour ago, Whipped500 said:

I've been keeping an eye on it since new. It was at the correct level when new, but now it is low.

How many miles on it?

Has it ever been topped up (cold of course)? 

 

How's the other tank doing?

 

 

[Whipped500]

2 hours ago, redwngr said:

How many miles on it?

Has it ever been topped up (cold of course)? 

 

How's the other tank doing?

 

 

14,600.

Charge tank is fine/maintaining.

Never been topped off

Edited March 7, 2022 by Whipped500

[Rubyralph]

I’m having the same issue with my LM2 at 8K miles. Had the dealership check for leaks but the only way they will confirm a coolant leak is to document it over some miles. I made the mistake of topping off both tanks twice myself. I’ve noticed a coolant smell in the garage after diving, some said this is normal, I never had a vehicle smell of coolant unless there was a leak in 50 years of GM ownership.

[youcantkeepup!]

You are smelling the DEF. It smells the same

[Whipped500]

2 hours ago, youcantkeepup! said:

You are smelling the DEF. It smells the same

If it smells the same, then I can't be sure what I'm smelling...but as my tank shows, it is losing it somewhere. 

[tim27577]

No it is not DEF it’s coolant. My’n has 39k and same issue some days driving long distances after I park it. And shut off. I can clearly smell it maybe 1 time out of 10. I’ve lost coolant in my tank also. The purge tank is fine. Hasn’t lost any. 

[silveradosid]

my 2020 had this problem, it was the rad leaking, took the dealership 2 days to find it. they agreed they could smell it just couldnt find it

[Bradyorlando]

I've got the same problem as well, 2021 model with 22k mi and have been smelling coolant when I park since new, no drips anywhere but my coolant reservior goes down over time, have had to top off several times. I wonder if it's a small enough leak that it evaporates first or something. 

[Spurshot]

Seems like it's fairly common.  My 99 1/2 GMC 2500 6.0L was losing coolant extremely slowly, but never dripped a drop.  I figured it was a leaky head gasket, since I'd read it was a problem with LS engines of the time. 

 

After I had sold it to a friend, he discovered a pinhole leak that opened when under pressure and evaporated as it sprayed/dripped on part of the radiator itself.   I believe it was in the plastic end tanks.  

 

Take a good look around the tanks with a flashlight, looking for dried coolant residue.

[silveradosid]

i never seen a drop on the ground either. they had to remove my fans to actually find the leak. it took them 3 weeks to get a rad and i just kept topping it up, but still never seen coolant on the ground

[Bradyorlando]

That's very helpful thank you, I will try checking my radiator and it's end tanks more thoroughly, I do seem to smell coolant the most around the radiator, and only when it's hot. Hopefully I can find it so I don't have to keep topping it off.

[seamus2154]

I have the exact same issue. I have a 2021. Since new I always smelled coolant. I am now at 17K and the tank is low and I am expecting the light to go on soon. I am over 18 months into ownership. Short trips, very hot trips, interstate trips, towing. I no longer smell coolant, but my tank is as yours. ??? Don't know where it went, and if it were a big issue I expected to find out already??? I do oil analysis and there is nothing in the oil. Truck run like top, not one issue