How's your all's coolant levels looking?

My truck has a little 12k miles and not much of a change to the level from new. but yeah there is always a good amount of fluctuation

 

I'm genuinely curious, what are those other factors? If the truck has sat all night and ambient temp differences in the morning are negligible, I'm struggling thinking about what else would be a factor.

 

I'm no expert so I may be completely wrong, but I would imagine that when you use the heater, coolant then has to flow to the heater core. Maybe its always circulating through there but what about when your thermostat open or closes doesn't it then alter the path of the coolant? wouldn't that affect the amount of coolant that then returns to the reservoir? I'm just thinking out loud. Could it be possible that there may have been air pockets that worked their way out and now the level is slightly lower? I think a better test may be to check the level at operating temp when the system is pressurized. If the coolant level when hot keeps dropping then that may indicate an issue. Like I mentioned I'm no expert just food for thought. either way as I mentioned earlier if your concerned just have the dealer check it. I think a remember a thread a while back about one member that had a small coolant leak from one of the hoses near the intake that was evaporating from the heat of the engine leaving no leaks and making it somewhat of a mystery. good luck

 

I found a link not sure if this one was the same as the one I spoke about before or a different situation. Maybe this will help https://www.tacomaworld.com/threads/2017-tacoma-coolant-leak.492860/

 

Nice! I'll see if I can spot anything around there.

 

It is normal for about 1” of fluid to disappear since the coolant expands and contracts. But if more than that, get it checked out. Especially if you can smell it.