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Engine Coolant Question

I have a 2006 Toyota Corolla that’s a little low on engine coolant. The manual claims I should purchase Toyota coolant, so I bought a gallon of “Toyota Super Long Life Coolant”.

Now, my question is this: do I need to dump the old coolant before putting this new coolant in? I’m not sure what type of coolant is in there right now, but if I had to guess, I’d say it’s probably some basic/standard coolant. I just don’t know if it’s OK to mix them.

You can just top it off. Read the bottle to see if it needs to be mixed with water, usually at a 50/50 ratio, before being added to the system. Some are pre-mixed and ready to use.

Also, read the manual under service intervals to determine when to take it in for a coolant change. It should be clearly stated. Typically, since the coolant is drained then engine and radiator flushed with clean water during this service, it is a good idea to change the thermostat and radiator cap. They also check the condition of the radiator and heater hoses.

Thanks. It’s a pre-mixed coolant.

If it is just a little low, you can just add a little water. I would not use more than say a pint.

If you bought this car used, there is no telling what kind of coolant is in there unless only Toy dealers touched it. If universal coolant was added, you should only trust it for a max of 3 years. I think that you can use Zerex Asian Vehicle Anitfreeze / Coolant for a lot less coin than the dealership stuff. Unfortunately they appear to have only 50% premix. NAPA, and others have Zerex.

It it were mine, and I did not know the history, I would change it to Zerex or Toy coolant when weather permits. Since you have a gallon of Toy coolant, you might want to go that way even if you have to buy a little more. The coolant is a lot cheaper than the parts that might be compromised by bad coolant.

Flush, flush and flush with tap water. Do one or more drain and fill cycles with distilled or deionized water and then add (100%) coolant to taste.

Is the coolant in the car the same color (red, I assume) as the new coolant?

It actually looks relatively pink.

Yeah, I think I might just take the time this weekend and flush out the old coolant.

I’ve never actually flushed out a radiator before, but I’m pretty sure I can figure it out. I’ve been researching it online, and I think I found a pretty good step-by-step:

Does that basically cover it?

Those instructions from eHOW could be better written.
If the radiator doesn’t have a draincock, disconnect the lower radiator hose.
Drain the radiator and refill the radiator with water.
Turn cabin heater to HOT.
Run the engine until the engine temperature reaches normal. Shut the engine off, and let the engine cool.
Drain the radiator. Each drain removes about 1/2 of the old antifreeze/water mix.
Refill with 100% antifreeze. You need to use the 100% antifreeze to be able to get a mixture which is about 50 / 50 antifreeze/water.
{You could do the fill with water, run to hot, drain, refill with water two or three times to get the most of the old antifreeze our.]