‘22 ZR2 coolant smell

[landpilot]

So for the last few hundred miles or so, my truck has had a coolant smell when I park after driving for a hour or longer. I don’t see any obvious leak, and there’s no puddle under the truck. It also doesn’t appear there is any loss of coolant from the reservoir.

Anyone else noticed this on their truck?

 

[185EZ]

I noticed it on my 2023 but it was after they put in new lifters.
Never had the smell before
At first they said it was burn off from the work.
But it was always there and I noticed the over flow tank was over filled.
I had it scheduled for service but decided to trade it in

 

[DBAG]

So for the last few hundred miles or so, my truck has had a coolant smell when I park after driving for a hour or longer. I don’t see any obvious leak, and there’s no puddle under the truck. It also doesn’t appear there is any loss of coolant from the reservoir.

Anyone else noticed this on their truck?

6.2 or 3.0?

 

[landpilot]

Sorry I missed this.. it’s a 6.2L

 

[Fixinta]

Any luck figuring out what was causing the smell? Mine has recently started to smell like coolant after long drives and warmer ambient temps. 2024 6.2 w25k miles

 

[Duramax Joe]

Look down between your cooling fan and radiator along the edge of the radiator for wet grimy looking spot or have surge tank cap pressure checked both can cause coolant smell

 

[GatorZR2]

Any luck figuring out what was causing the smell? Mine has recently started to smell like coolant after long drives and warmer ambient temps. 2024 6.2 w25k miles

I have them same smells after long drives like the coolant is cooking. Don't really notice it on short trips. I have no visible leaks anywhere. I think it's related to the active shutter system. But as @Duramax Joe pointed out in picks, these wonderfully cheap radiator ends are prone to leaking.

 

[landpilot]

Any luck figuring out what was causing the smell? Mine has recently started to smell like coolant after long drives and warmer ambient temps. 2024 6.2 w25k miles

no, and it has stopped doing it… I’ve checked all over and don’t see any signs of a leak, and the coolant has never been low.

 

[Fixinta]

Seems to be enough pressure that the coolant expansion tank cap has a faint hissing on hot days or long drives. No visible leaking elsewhere. I let it cooldown for the day,, next morning removed the cap, had white residue/buildup around the underside of the cap. Cleaned it off, topped off the coolant(was low by 1/4” below max line), put the cap back on and havent noticed the smell since.

 

[AXE]

Might need to replace the cap or pressure vents. Not sure how it's rigged, but if it's building too much pressure that its blowing out, it isn't venting correctly. Also, might need to replace the thermostat if its boiling and building pressure the thermostat might not be working or the water pump isn't moving fast enough.

 

[Fixinta]

Picked up a new cap, will update after some errands later today.

 

[Fixinta]

Update, new cap, less smell. Scheduled and took in for warranty claim on the thermostat, only to get the truck back 2 days later with "we couldn't find anything wrong, no codes thrown by the thermostat" story from the service advisor. They said they pressure checked the cooling system, drove it 15 miles(confirmed on odometer), and could not replicate and did not smell anything. Guess next time I decide to drive 45 mins up to the mountains again, I will have to bring the service advisor with me.

 

[AXE]

Update, new cap, less smell. Scheduled and took in for warranty claim on the thermostat, only to get the truck back 2 days later with "we couldn't find anything wrong, no codes thrown by the thermostat" story from the service advisor. They said they pressure checked the cooling system, drove it 15 miles(confirmed on odometer), and could not replicate and did not smell anything. Guess next time I decide to drive 45 mins up to the mountains again, I will have to bring the service advisor with me.

Sounds about right! They probably have 100s of documented cases.

 

[Duramax Joe]

Sounds about right! They probably have 100s of documented cases.

Unfortunately alot of times for techs time is money so alot of them dont take the time to find and fix the problem unless it is staring them right in the face. And I wish GM had documented cases for stuff but again I think thats is one of their weakest links is tracking what other dealers around the country see cause sometimes that would make my life alot easier. We used to have a tool that we could see other cases that techs had sent in to technical assistance but GM deleted all of it and changed the whole system on us. Sorry for the long post and I am un no way defend the dealer he took his truck to just adding some info.

 

[AXE]

Unfortunately alot of times for techs time is money so alot of them dont take the time to find and fix the problem unless it is staring them right in the face. And I wish GM had documented cases for stuff but again I think thats is one of their weakest links is tracking what other dealers around the country see cause sometimes that would make my life alot easier. We used to have a tool that we could see other cases that techs had sent in to technical assistance but GM deleted all of it and changed the whole system on us. Sorry for the long post and I am un no way defend the dealer he took his truck to just adding some info.

I'm fortunate to have a really good dealer and I've worked with the same service advisor since 1997. One thing I've realized in the last few years is that everything has to go back to some GM warranty clown for approval and the dealer had less discretion. I think that's a huge gap in customer service to drive profits.

One thing I've never had to complain about is dealer service and support. Hell, I've even had GM Warranty parts that were out of warranty. I just haven't tested those waters recently.