Which Grade Of Fuel to use?
 

Forgive the n00b question.

I just picked up my new (Used) 2009 RX 350 - Pebble Beach Edition, a few hours ago. Although I'll have a ton of questions, one that's on the top of my mind is about the fuel.

Should I really put Premium fuel, into the tank?

I'm coming from a 2005 Corolla Sport, so you can understand the upgrade, as I've never had a vehicle like this before.

If I need to run Premium, I will. But can I use Regular Gas? Will I notice a difference, Will I mess up anything to run it, etc...? I filled up the last half of the tank, when I picked it up, with Premium, so I won't need to fill it again for another week, but want to get my homework done now.

Any info, is deeply appreciated. Thanks in advance.

What does your owners manual say about the fuel type?

I run premium only.

Lexus says to use premium fuel. I am sure they have a good reason for recommending that. This subject has been extensively discussed on this forum. The "Search" button is your friend.

I've used 87 for a long road trip last weekend. It worked perfectly fine. I got the same MPG, though a slight drop in hp.

Follow the owners book + what it reads on the Fuel door

Shell 93 in my vehicles.

not that i dont doubt you, but how the heck would you know that? did you put the vehicle on a dyno with premium, and then with regular?

i think you mean it "feels" like less hp, this is called the placebo affect

Obviously, I was "subjective" when I said that. There's no scientific comparison. I just felt like I had to press the pedal harder with 87 octane.

I have run 87, 89, and 93 octane in mine. It does seem that the gas pedal reacts sooner with the 93. Gas mileage very close in all 3 grades. I use a minimum of 3 tanks each to compare. No knocks with the lowest 87, even in the smokies with 4 people on board. I now use 93 because I like the accelerator quicker action feel better. To each his/her own. Good luck!!

My 2 cents.. You paid for a premium vehicle, why skimp on the fuel. The manufacturer recommends premium fuel so that's what I run..

I know this may sound retarded and all,but mine seems to like the 87-89 octane the best ? :confused: Totally opposite of my 01,that thing ran the best on premium. Maybe it`s because the original owner used 87 for 59,000 miles ? And then had the tsb done for the transmission lag ? Who knows,I dont know. BTW,it`s not that I`m too cheap to use premium,if it ran best on it, I would use it. But this is the really screwey part,even the transmission shifts the best on the lower octane. Go figure ?

Ding,ding,ding...we have a winner!! :thumbup: :)

its like taking vitamins for yourself. you really dont know if its helping you or not. just follow the doctors advice right? me i just put premium because i beleive its safer for the catalytic converter and the extra mileage i get i treat it as a bonus. my rx 330 still runs like brand new with 72000 km. i use amsoil oil for the first time and runs quieter now. i love this vehicle. no trouble at all for a 5.5 year old vehicle and very good on snow.

This has been around and come around several times.....Put any thing you want too in your tank....Just like what you eat...But what is best for you and your car is what they recomend...Be it Lexus or you Doctor...