Is your Tacoma consuming coolant?

[saerandy]

I was under the hood checking the oil level today (cold engine) and noticed that my coolant level was about 1/4 to a half inch below the low mark which surprised me since Toyota did the last oil change at around 20,000 miles. (I would assume they would top off) I’m now at 25 and just did an oil change a week ago but didn’t really glance at the coolant level when I was refilling it.

I never really considered to regularly check that stuff too closely since the truck is so new, but I’m now wondering if anybody else has noticed some consumption? I do drive Long highway miles occasionally so not sure if that might have to do with it?

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[EatMyTaco]

Coolant is checked hot.

run it till the coolant starts being pushed back to the tank. See if it’s still “low”

 

[maxx075]

Yep, I've had (have) this issue. Every now and then I'll get the sweet smell of antifreeze when I turn the truck off. Took about a year and a half, but it slowly got down to the low level.

Never noticed any leaks, and I've checked to see if there were any, but didn't see any around the fan (where there have been known connection issues).

Took it to the dealer and they filled it back up and just said to keep an eye on it.

Not sure where it's evaporating/leaking/being consumed from though. Definitely something to watch.

 

[395North]

Yep, I've had (have) this issue. Every now and then I'll get the sweet smell of antifreeze when I turn the truck off. Took about a year and a half, but it slowly got down to the low level.

Never noticed any leaks, and I've checked to see if there were any, but didn't see any around the fan (where there have been known connection issues).

Took it to the dealer and they filled it back up and just said to keep an eye on it.

Not sure where it's evaporating/leaking/being consumed from though. Definitely something to watch.

Same here.
Bought some OE coolant and top off every so often.

 

[saerandy]

Coolant is checked hot.

run it till the coolant starts being pushed back to the tank. See if it’s still “low”

I'm pretty much 100% sure you are not supposed to check it hot, but cold so you can add to appropriate level without the system exploding in your face.

 

[EatMyTaco]

I'm pretty much 100% sure you are not supposed to check it hot, but cold so you can add to appropriate level without the system exploding in your face.

You won’t get coolant in your eye from the expansion tank. Opening it isn’t like opening the radiator.
also why the tank is clear with high/low marks so you don’t need to open it and visually check.
Coolant expands when it’s hot, ergo expansion tank

 

[395North]

You won’t get coolant in your eye from the expansion tank. Opening it isn’t like opening the radiator.
also why the tank is clear with high/low marks so you don’t need to open it and visually check.
Coolant expands when it’s hot, ergo expansion tank

While that is true , what is special about the 4th gen that suggests it should checked when hot? Cold seems to be the correct method.

 

[Andrace]

Coolant level is checked cold, see attached service guide.

 

[LincolnSixAlpha]

Yep, I've had (have) this issue. Every now and then I'll get the sweet smell of antifreeze when I turn the truck off. Took about a year and a half, but it slowly got down to the low level.

Never noticed any leaks, and I've checked to see if there were any, but didn't see any around the fan (where there have been known connection issues).

Took it to the dealer and they filled it back up and just said to keep an eye on it.

Not sure where it's evaporating/leaking/being consumed from though. Definitely something to watch.

Mine is the same, when I pull into the garage, I can usually smell it a few minutes after I turn the truck off. It's been doing that since new but never see any leaks on the floor or anywhere else. I've even topped it off with a small amount. I'm curious about this, but can't seem to deduce what the deal is with this coolant nonsense. Gotta be honest, getting tired of smelling it!

 

[lpsoldia311]

Al the Toyotas I've ever owned (and most other cars I'd presume) have the expansion tank open to atmosphere, some more prominently than others.

When the coolant heats up during normal running/driving there's no air to compress inside the engines coolant system, so it will automatically open the radiator cap pressure valve around 15psi and then slowly flow that excess hot coolant into the expansion tank. That slow heating/filling and cooling/draining of the tank is what raises and lowers the levels of the coolant inside the tank and so it must be vented to atmosphere in order to allow that expansion, not to mention it'll over time boil away some of the hot water in the coolant mix just due to the heat and evaporation.

That's generally why if you smell it at all it'll be after a hot or long drive. Keep the tank filled where needed.

 

[sabinjo]

Traded in my Jeep Gladiator for a new Tacoma, and one of the many issues I had with it was a frequent smell of coolant after driving and parking. Asked about it during an oil change but they couldn't find anything and it wasn't getting noticeably low or had any leaking. A few weeks later when the weather got colder on one instance of getting the smell I swear I saw some steam coming from the grille area.

Brought it back in and sure enough there was a pinhole leak that they were finally able to find at the end of one of the smaller coolant hoses that had a metal piece at the end of it. I would have never found it on my own unless/until it got bigger but I guess they were able to test it under pressure or something and found it.

Fast forward to the last few weeks and 9k miles and I've started to all of a sudden intermittently notice a coolant smell from the Tacoma at the front of the truck after driving.

I'm having deja vu all over again and was about to come here and post a question about it to see if anyone else has noticed the same thing.

 

[BLtheP]

You won’t get coolant in your eye from the expansion tank. Opening it isn’t like opening the radiator.
also why the tank is clear with high/low marks so you don’t need to open it and visually check.
Coolant expands when it’s hot, ergo expansion tank

It’s not an “expansion tank,” it is a degas bottle. Totally different and it will explode on you if you open it hot.

 

[BLtheP]

Al the Toyotas I've ever owned (and most other cars I'd presume) have the expansion tank open to atmosphere, some more prominently than others.

When the coolant heats up during normal running/driving there's no air to compress inside the engines coolant system, so it will automatically open the radiator cap pressure valve around 15psi and then slowly flow that excess hot coolant into the expansion tank. That slow heating/filling and cooling/draining of the tank is what raises and lowers the levels of the coolant inside the tank and so it must be vented to atmosphere in order to allow that expansion, not to mention it'll over time boil away some of the hot water in the coolant mix just due to the heat and evaporation.

That's generally why if you smell it at all it'll be after a hot or long drive. Keep the tank filled where needed.

This is not all the other Toyotas you've owned. The radiator doesn't have a cap anymore, and the system no longer has an expansion tank. It has a degas bottle and uses that bottle to constantly purge air from the system and it runs pressurized coolant through the "reservoir" to do that.

I can't speak to whether or not coolant consumption is "normal" anymore as I have not noticed mine going down.

Cars have been going this route for a while. Nissan started doing so in the Frontier in 2005. It is more finicky and I don't understand the benefits, but it is what we get these days. The third gen Tacoma and earlier had the typical expansion tank which is very simple and you can open the tank at any time. Those days are gone now, we don't have that system anymore.

 

[sabinjo]

This is not all the other Toyotas you've owned. The radiator doesn't have a cap anymore, and the system no longer has an expansion tank. It has a degas bottle and uses that bottle to constantly purge air from the system and it runs pressurized coolant through the "reservoir" to do that.

I can't speak to whether or not coolant consumption is "normal" anymore as I have not noticed mine going down.

Cars have been going this route for a while. Nissan started doing so in the Frontier in 2005. It is more finicky and I don't understand the benefits, but it is what we get these days. The third gen Tacoma and earlier had the typical expansion tank which is very simple and you can open the tank at any time. Those days are gone now, we don't have that system anymore.

Question since I don't know anything about this. If what you describe is the case and it's constantly purging air from the system, could that be the reason some of us smell coolant at times and is totally normal?

Also, could it be that the air coming out also contains vaporized coolant or something which would be why over time it would get low? Again, I'm no scientist or know crap about any of this, just some common sense thoughts.

 

[BLtheP]

Question since I don't know anything about this. If what you describe is the case and it's constantly purging air from the system, could that be the reason some of us smell coolant at times?

Not sure. I had two 2019 Frontiers with a nearly identically designed system (as are most modern cooling systems these days) and I did not notice any whiffs of coolant from those. I have noticed some coolant whiffs a few times in this truck, and I'm not really sure why.

I'll have to look closer at the Tacoma when I get a chance, but on the Frontiers, the "radiator cap" with the spring loaded pressure release was on the plastic degas bottle. However, the little relief hose nipple that came off of the cap's venting output pointed into the fender well, so maybe if that one did have an odor, I just never noticed it because of where it pointed? The Tacoma doesn't have the exact same relief so I'm not entirely sure on this one. The Frontier had the bottle on the right side where our fuse box in front of the battery is. Mounting the degas bottle on the radiator (like how the Tacoma has it) is a more modern concept that I don't have much experience with...same modern style design principle though.

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