i posted this in the 2nd gen. but really don't get an answer. i was wondering if i could use this stuff in my is350 safely without problems.

 

According to them, it should be fine...

IMO, use what is recommended for your car...

I might add though, that they don't recommend it... according to their site, its designed for large displacement engines and high outputs... the IS350 doesn't fall under either of those classifications...

 

The OEM oil pump might not provide enough head to pump the "heavier" oil to certain part of the engine. It is a tough call and certainly risky....