[Chilow]

I recently drained/refilled the coolant using the OEM stuff and made sure all the bubbles were out. I checked the reservoir level everyday for about a week and topped off to the F line as necessary until the coolant level remained the same. I was checking something in the engine bay yesterday and noticed that it dropped about half an inch. Should I be concerned?

[Captsolo]

I assume you are talking about the overflow canister.

Check it twice a week and add if you have to.

Don't let it overheat.

In my 2005 4runner (150,000), coolant level stays the same month after month

Still starts and runs great. Zero maintenance almost.

I want 500,000 miles. Short miles because the car is in Nassau Bahamas. No highways.

[Chilow]

Yes, the overflow. Weird part is the coolant level stayed consistent for about 1-2 months since I've done it.

[00Sebby]

Likely not a big deal. It is a pressurized system and the overflow tank is only there to allow coolant to be expelled and drawn back in without wasting it. If the engine is warmer, there is more pressure and the overflow tank may be more full. If the engine is cold, then less pressure and less coolant in the overflow. Changes in weather and how cold the vehicle gets can change the level slightly.

If engine temp is normal, you don't smell coolant (leak), and you don't have excessive/continuous visible exhaust vapor or muddy looking oil, all is well.

[seatia]

Try to check it at a known time when it is completely cold such as first thing in the morning before first starting it.

A partially warm engine could account for 1/2" in the bottle.
Even then, it's nothing to worry about.

[LandCruiser]

I wouldn't sweat it.

Check it every once in a while at the same time of day and similar engine temp to look for changes and if it's still pink.

[Captsolo]

Originally Posted by Chilow

Yes, the overflow. Weird part is the coolant level stayed consistent for about 1-2 months since I've done it.

If it stays the same for 2 months, you are ok and can't have a blown HG issue.

Still check it 2 times a week and watch it forever.

[Tbasse01]

Keep a eye on it

If it got cold out like here in Ontario it will drop a bit and same in summer it will rise a bit in the overflow

My guess is just some air you did not get out


Troy

[Chilow]

OK - I checked pretty much everyday like some of you have suggested. I checked around the same time (after I've driven for a while and the engine still hot). The coolant level was right underneath the full line. I checked in the morning (before turning it on) and it was between the full and low lines.

Should I add more coolant while the engine is cold/not running to the full line? I don't think there's any issues with it being overfilled, looks like there's a good amount of empty space above the full line.

[fkheath]

Originally Posted by Chilow

OK - I checked pretty much everyday like some of you have suggested. I checked around the same time (after I've driven for a while and the engine still hot). The coolant level was right underneath the full line. I checked in the morning (before turning it on) and it was between the full and low lines.

Should I add more coolant while the engine is cold/not running to the full line? I don't think there's any issues with it being overfilled, looks like there's a good amount of empty space above the full line.

If it is above the add line (cold) there is no need to add coolant. Since coolant expands and contracts with temperature, you see those variations depending on the coolant temp. That is completely normal. If the engine is really hot (fast driving, uphill driving, or towing), then the coolant may be a bit over the full line. That is OK as well.