Antifreeze Smell in Cab…but No Leak?

[wradar]

This week, after the truck was parked and covered for about two weeks, I got in to drive it and immediately noticed a strong antifreeze-like smell. Immediately suspecting a heater core leak, I called the local dealership to see what a replacement would cost before I brought it in to start troubleshooting. They said it’d be $5700.

After I regained consciousness, I took it to an independent mechanic for diagnosis and a quote. They said they could definitely smell the odor, but they couldn’t find any evidence of a leak (moisture) on the passenger floorboard, and it passed a coolant pressurization test. They asked to keep it overnight to do some more diagnosing in the AM, but the mechanic acknowledged he doesn’t know what it could be if not a heater core leak, but he doesn’t want to jump into that costly repair if he’s not sure that it would solve the issue.

Any other ideas?

 

[SD Rebel]

Maybe a small intermittent leak has started, just enough to smell but not enough to wet the floorboards. Won't take much to get a whiff inside the cab.

Unless you need the heat, you may want to just get a permanent heater core bypass and avoid the high cost of repair if that becomes the problem. I don't think I've ever used my heater, but I live in a warm climate and relatively fat, so not a issue. That will be my plan should my heater core leak out of warranty.

 

[n8zcc]

I had a parallel issue, I could smell the order of antifreeze but only after driving. It turned out to be what they call an evaporative leak. What this means is the antifreeze that leaked evaporates so you do not see wet from the antifreeze but you get the smell. What I did was put a black light-sensitive die in my cooling system. After a few days, I took a black light and started looking. Sure enough, I found the leak. It was from the thermostat housing, one bolt was not torqued correctly.

$5,700, I would have passed out too.

 

[Jako]

I had a parallel issue, I could smell the order of antifreeze but only after driving. It turned out to be what they call an evaporative leak. What this means is the antifreeze that leaked evaporates so you do not see wet from the antifreeze but you get the smell. What I did was put a black light-sensitive die in my cooling system. After a few days, I took a black light and started looking. Sure enough, I found the leak. It was from the thermostat housing, one bolt was not torqued correctly.

$5,700, I would have passed out too.

Thanks for the info. There have been previous posts on the anti freeze smell. Glad you resolved the issue.

 

[wradar]

I had a parallel issue, I could smell the order of antifreeze but only after driving. It turned out to be what they call an evaporative leak. What this means is the antifreeze that leaked evaporates so you do not see wet from the antifreeze but you get the smell. What I did was put a black light-sensitive die in my cooling system. After a few days, I took a black light and started looking. Sure enough, I found the leak. It was from the thermostat housing, one bolt was not torqued correctly.

$5,700, I would have passed out too.

Thanks for this info, that's a solid idea. Where can you get the dye?

 

[wradar]

Unless you need the heat, you may want to just get a permanent heater core bypass and avoid the high cost of repair if that becomes the problem.

Good idea, but we definitely live in a place that still gets winter, so we use it fairly often.

 

[jamiehughes]

Thanks for this info, that's a solid idea. Where can you get the dye

most good auto parts stores carry it.. i work at a napa location and we stock all the dyes..

 

[Cbty2050]

They said it’d be $5700.

Was that just a heater core and coolant? Book time is 10hrs(or so).

 

[wradar]

Was that just a heater core and coolant? Book time is 10hrs(or so).

They said that was “the whole job” to replace the heater core. I didn’t get a written quote, just the verbal.

 

[wradar]

Update: mechanic did a second pressure check on the coolant system and it passed. He acknowledged it could be a small leak from the heater core that is only detectable by smell at this point, but was very reluctant to dive into replacing the core without better assurance this was the source of the smell. He also said he called a local Dodge dealer and they told him they’d only seen one or two trucks at this age/mileage have a heater core issue, which wasn’t enough to convince him one way or another.

So, plan at this point is to drive it and monitor fluid level in the reservoir, keep an eye out for dampness on the passenger floorboard, and perhaps do the dye option in the coolant myself. (That was the only thing that raised my eyebrow was the technician’s assertion that dye wasn’t an option because it’s “only used for AC systems.” So…I’m just going to assume he didn’t follow what I was asking or something, as using dye is clearly an option for finding a coolant leak.)

On the plus side, this shop said a core replacement would only run $1700 parts/labor, so if I go that route I’ll likely use him (unless I’m able to get Stellantis to give me a significant good-faith discount on the dealer doing the work).

 

[SD Rebel]

Update: mechanic did a second pressure check on the coolant system and it passed. He acknowledged it could be a small leak from the heater core that is only detectable by smell at this point, but was very reluctant to dive into replacing the core without better assurance this was the source of the smell. He also said he called a local Dodge dealer and they told him they’d only seen one or two trucks at this age/mileage have a heater core issue, which wasn’t enough to convince him one way or another.

So, plan at this point is to drive it and monitor fluid level in the reservoir, keep an eye out for dampness on the passenger floorboard, and perhaps do the dye option in the coolant myself. (That was the only thing that raised my eyebrow was the technician’s assertion that dye wasn’t an option because it’s “only used for AC systems.” So…I’m just going to assume he didn’t follow what I was asking or something, as using dye is clearly an option for finding a coolant leak.)

On the plus side, this shop said a core replacement would only run $1700 parts/labor, so if I go that route I’ll likely use him (unless I’m able to get Stellantis to give me a significant good-faith discount on the dealer doing the work).

Sounds like a plan, though did you mention the year and mileage of your vehicle, curious to know.

 

[Cbty2050]

It's not an uncommon issue, I have seen this at lower mileage. Last one I did was for a family friend at 2020 @ 50k miles. Very small leak, the core had staining on it.

 

[wradar]

Sounds like a plan, though did you mention the year and mileage of your vehicle, curious to know.

2021 with about 43k.

 

[wradar]

It's not an uncommon issue, I have seen this at lower mileage. Last one I did was for a family friend at 2020 @ 50k miles. Very small leak, the core had staining on it.

Is there a common point of failure?

 

[Cbty2050]

Is there a common point of failure?

Along the side tank seams/edges.