Hello,

I have a 2008 Lexus rx400h with 180k miles. Everything is relatively good but recently I noticed that my engine coolant reservoir (connected to my radiator) was empty. I've attached a picture of the reservoir. I put some coolant in the reservoir but am not sure if that was the correct thing to do. I have not noticed a coolant leak, I'm not sure how long that reservoir has been empty. Everything runs fine. My rig has run just a touch over the middle temperature indicator line on the dash and has done so without issue for many miles.





Any advice here? Did I mess up the coolant system or will it be okay?

Thanks in advance. I'm learning a lot through this process.

 

Very likely you need a new radiator. They tend to leak but not enough to drip the coolant dries out before reaching the ground.

 

What he said... I had the same thing happen recently I noticed what looked like pink silly strong on the driver's side by the bottom radiator hose, once I removed the radiator to give it a good look it was slowly leaking on both sides. This isn't a tough repair make very sure you go with either the OEM or a Kyo whatever the name is brand or you could be replacing it again very shortly

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when was the last time you did any type of coolant service?
If you haven't touched it for 5+ years, I'd say it's a possibility that some may have evaporated.
I know many will say it's a closed part and shouldn't disappear, but in my experience, all my news cars had some type of loss in the first 5-10 years.

I'd just keep an eye on it. You may need to refill it again couple more times if it was really low.2

 

Definitely has been 5+ years at this point. Everything else is running as it should be. Thanks for the reply.

 

Do you have a radiator replacement video to reference? I have not been able to visibly see any leaks.

 

if i does not need refilling again you do not have a problem

 

Do I need to burp any air out after refilling since it was completely empty?

 

no just fill it up. you only need to :burp if radiator is drained

 

Have you checked below the radiator? I'd pressure test the cooling system,as the coolant doesn't just disappear, similar to the a/c refrigerant, unless ttheres a leak somewhere......You have a 3mz,so iit could be one of the coolant hoses below the i/m as well.

 

Not necessarily could be fine in warmer weather then start leaking again. 99% chance the rad is leaking best case it leaks slowly and doesn't blow up at a bad time.