I drained the radiator only at 55,400 miles in TX on August 25, 2024.
Less than a gallon of Toyota pink SLLC. I used the (Lisle?) inexpensive funnel kit to refill and burp system. I replaced radiator cap with new OEM. I checked over several days to make sure the overflow tank was at appropriate level - hot and cold.
I’ve noticed on multiple occasions since 2019 that the overflow tank was low or pink crust on the overflow tank cap (which will be replaced). Dealers have typically just topped off the overflow tank w/pink SLLC iirc. No other diagnosis or repair. At one point the overflow tank was very low and I advised the Dealer in TX. They just added coolant. I thought maybe it was evaporation over time in TX heat. But, then again CA was hot too - but a dry heat
I am at 63k miles right now, 6000 ft elevation give or take, and coolant overflow tank was 1/4 to 1/2 inch below max level. Then drove 10 min to Dealer and when I opened hood for SA it was 1/4 inch over max line. But, still plenty of room in the overflow tank.
I had not checked level since the d&f. The overflow tank and radiator are covered by a plastic cover with a dozen push pin connectors. And, I don’t routinely remove that cover for most other diy servicing.
Here is a pic from today b4 driving to Dealer. Sorry, should have posted these earlier.
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Here is pic from August after I had completed d&f and checked level for 2 days.
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Coolant test strip on Aug 10, 2024 - 15 days before d&f.
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