Coolant Flush Or Just Replace?

[prix]

Installed new radiator and fan shroud at end of 2007 so got new Toyota long-lasting coolant at that time. Since then, the car hasn't been driven much (10K miles roughly). Probably past due to change the coolant. The lexls.com tutorial shows 'flush' and 'non-flush' procedures. Which do I need to do (have done)? What are some of the ways that contaminants can get into the system? The only thing that has been done (to my knowledge) was done yesterday, when the tech topped off the reservoir, which was right at the 'minimum' level. He poured up to 'max' (with the engine off/cold).

[lenore]

I would do nothing.The coolants of today will last an easy 5 years as long as you have no cooling problems...contaminants are induced from the cast iron block,and electrolysis between many of the the dissimilar metals, but if no water other than distilled is added the minerals should be fairly stable. The no silicates coolants of today are just plain fantastic....They lubricate and keep corrosion to a minimum.

[prix]

It's been four years, two months. I guess there's no rush. Sounds like I can do a drain and fill then when I am ready. Thanks.

I would do nothing.The coolants of today will last an easy 5 years as long as you have no cooling problems...contaminants are induced from the cast iron block,and electrolysis between many of the the dissimilar metals, but if no water other than distilled is added the minerals should be fairly stable. The no silicates coolants of today are just plain fantastic....They lubricate and keep corrosion to a minimum.

[LXPearl]

Drain and Fill works well using the Toyota Long Life concentrate with distilled water, or the premix.