RX400h 2008 fuel type E10

[jxx]

Can/Should I use E10?

[bazzle]

Lexus says you can 🙂

It isnt as efficient as 91 but is cheaper.

If your going to use it I would alternate with normal fuel for peace of mind.

In the end its your call.

[jxx]

that's somewhat same what Lexus said, 

They said " E10 fuel is suitable for your vehicle however we recommend to use 98 octane premium fuels for optimum performance and reliability later in the vehicles life.

You can also use 95 octane premium fuel as a second choice, please never use 91.

If you were to use E10, please only use it maybe once in a while, one tank of E10 to ever two tanks of premium fuel perhaps" 

[bazzle]

Just stick to 95.