Coolant Low on a 2018 4runner

Yes

 

Any update?

I bought my 2019 4runner with 56k miles. After couple months of using the car (multiple long trips above 4 hours), realized that the coolant level in reservoir was below “L” line, just like yours. The engine never overheated, even in hot weather. I did a test to check the head gasket, turned out fine. I did a flush & fill with new coolant, topped reservoir at “F” line.
After couple hundred miles has started to drop a little.

 

Every Toyota I've ever owned has very slowly used coolant. I think maybe evaporation.

 

How exactly did you do a flush and fill?

 

you don't flush, proven no benefits to it. drain radiator from drain valve, once it stopped, close valve (have to say that) and fill it roughly same amount (using special funnel from AutoZone). 1Gal from Dealership.

 

My bad. I meant to say I drained the coolant and filled it with the same amount, burped the air out.

 

When I did my drain and fill and new thermostat, even after I burped it, it took about 500 miles before all the air got out and the level stopped dropping.

 

Interesting. I guess I’m going to observe it for a while.

 

Yeah, even took it to a reputable shop and they burped it after 200 miles of my drain/fill. They got some bubbles. I put blue masking tape to measure cold level. Stop moving like I said around 500ish miles. I of course verified there was no leaks, etc.