Hi. FIrst yes I have been searching the forum and googling for an hour.

No issues. Everything has been working in the car. I do believe the CEL has been on for a very long time.(moms car)
Doing an oil change, and upon inspecting belts, I don't see any!

I see two large serpentine pulleys on the crank.. I'm looking, but really can't see any other devices with pulleys
. Is it possible this vehicles doesn't have any external belts?

After searching I get more confused.
Does the RX450h share the same engine parts as the GS450h? More so than the rx 350-400s?
I'm not sure the belt diagrams I have located are correct either. If anyone has the proper one or a link? I'd appreciate it.
Are there any service manuals online?

 

I am not sure if there is something on the drainplug. It looks black, but cant remove it. I have crush washers from Hondas that are a little bigger. Should I use them or go without anything?

 

First of all there are no belts external on hybrids....pulley is just the non used portion of this engine which is used thru out Toyota/lexus line of cars. Replace the crush washer on your drain plug with new. it is aluminum with felt washer .

 

Actually, my 2012 HiHy, which is same power train as RX hybrid, had ONE belt. Water pump. Far I know, even 2018 model has same belt. I am pretty sure you also should have it. It's called auxiliary belt or drive belt 99367C0810 $22.63

V6-3.5L (2GR-FXE) Hybrid

 

The water pump is turned by the timing belt for the 06-08 RX400h. There is no accessory belt. Just the harmonic balancer which has a pulley on it which is not used.

 

My demise is your gain! Here is a picture of the timing belt and the water pump. This is the only belt as stated.

 

I think air-conditioning compressor is electric so no belt. Water pump is driven by timing belt, probably why this one still has timing belt and not chain.
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