Helius

Recently, I drained my radiator and refilled it with Toyota's Super Long Life Coolant. As I was bleeding/burping out the air in the system using my homemade bottle funnel, the fluid in the bottle turned red, or perhaps dark dark pink! The coolant that I drained out was also a similar color and itconfused me as to which coolant was previously in my coolant system.

The Toyota's Super Long Life Coolant Turned is light pink. It was light pink when I initially filled the radiator, as well as, the bottle funnel in order to burp the system more efficiently. After I turned the car on, more fluid went inside and small bubbles starting coming up the funnel. Soon, it became slightly foamy with all the tiny bubbles and I realized that the coolant had turned dark pink/red and was also warm to the touch.

Has this happened to anyone else? Does the coolant change color as it warms up? Is this normal?

Thank you.

LeX2K

Pink fluid looks odd in the black container I think that's what you're asking about. If the coolant turned colour in the rad then there must have been some red coolant in the system. Check the colour in the overflow that's the best way.

Helius

I have been checking the radiator and the reservoir tank daily to see if the coolant level has dropped and needs to be topped. Fortunately, the radiator has be completely full and the reservoir only needed to be refilled once. Although, I am slightly concerned that the color of the coolant in the radiator is light pink, whereas the coolant in the reservoir is dark pink or red.

My engine temperature has not spiked and remain at the halfway mark of C and H of the temperature gauge when driving for some time.

Should I be worried about anything?

Oro

I wouldn't worry about anything, and nothing is going to go bad suddenly.

Did you buy your car new and are certain it had ONLY the SLLC ('pink') in it from new? Or is there a chance red was added in the past, like from a bottle of Zerex Aisan or the factory Toytota Red? The red is far more common in the aftermarket, and cheaper. There's MUCH debate about whether it's a good idea to mix, and I don't know the definitive answer. Regardless, lots of people have done it and it's not a grenade where it suddenly gels like some other mixes (trad. green and Dexcool, e.g.). Also, the color can change slightly over time and look different in the filler neck vs. through the plastic in the expansion tank.

Whatever color is in the expansion tank is also the color in the system; they mix when the engine is hot and the filler neck cap opens under pressure.

Helius

I did not buy the car new, so there is a chance that red colored coolant was (and is) already in the system. My 2005 Lexus ES 330 has a coolant reservoir tank, I am not sure if that is the same as an expansion tank or an overflow tank, or if my car even has those tanks, however, the reservoir tank has redish colored coolant in it.

I am hoping that everything will be alright. The car is driving normally without over heating in 100 degree F whether on short trips. I have yet to make longer trips, but once again I am staying positive as my car is driving very smoothly.

Oro

Expansion tank = reservoir = recovery tank, etc.

I am most familiar with the term "expansion tank" as that is what it really does. It does not act as a reservoir for extra coolant to enter the system if you lose some. It is to catch the expanded fluid when hot and pressurized, and then feed it back later. Thus, "expansion" tank. I think German car manuals call it "recovery" tank in parallel to the expansion concept since that is how the German is translated. Not really important, but just explaining why different terms are encountered.

I'm going to guess at some point, someone cheaped out and did not want to pay the high price for pink, or a mechanic got lazy and put Red in when they should not have. There used to be a TSB (tech service bulletin) from Toyota saying this was OK as they were OK to mix. This was very early on, like 2003. Since then, the TSB is gone and general consensus is NOT to do so since they are in fact different chemistry and not wholly compatible. However, it's been done a lot and there are no reports of massive numbers of radiators corroding, or plastics softening and decaying (these things DO happen when you mix some coolant types - I have experienced it).

Here's the lesson: If you buy a used car and go to add more coolant, ADD WHAT IS ALREADY IN THE SYSTEM, not what the manual from 15 years ago recommends. Because you simply don't know what was done. If you have opened your system and it was green, adding pink would have been very bad. The car won't stop running soon, but the system WILL start clogging and in a few years you could have a clogged radiator, coolant passages, or failing heater valves, cores, or radiator necks. This is all common and could be avoided, sadly.

So, re-reading your first post, you never said what color the coolant was you drained out? Coolant does not really change colors as it ages; the dye(s) don't degrade/get consumed like the active ingredients do.

As a corollary to the "lesson" above, if the existence of non-original colored coolant worries you (and there's reason it should), then do a very thorough, thorough flush with copious amounts of water and multiple drains, then fill with your desired coolant. I did this on our 4ES (2002), which actually had green in it 2nd hand when bought. I knew this was troublesome as anyone who would likely do that, it would be highly unlikely they would do it properly with adequate flushing and distilled water. I did that, and set a proper fill with red from concentrate (you have to allow for residual water in the heater core, so filling with pre-mix will automatically make it 35/65 or 40/60 at best, not 50/50). My radiator neck still rotted away 3 years later because of the bad reaction from the prior wrong fill. If I had stuck with green, it still would have done so, just probably 1 to 2 years sooner.