CJITTY

on premium, just got back from Memphis home to Atlanta @ 80mph and computer said 26.8 and I went about 365 on 1/2 tank..I'm not complaining. I get better mpgs when it is cold out and not running AC..closer to 29mpg on that same trip. I also have the 20s on with stagger in back, so that may shaved a touch off my mpgs, but not enough to lose sleep..we get excellent mpgs for this land yacht and horsepower, no complaints from me

ghenley

I just came back to Atlanta from Jacksonville and got 30 mpg according the computer. I've always been happy with the highway mpg for such a large car.

Greg

Nospinzone

Now you've lost me. At 72-75 mph the engine is only turning about 1700 rpm. In order to get 4500 rpm at that speed you would have to manually keep the transmission in 4th or 5th gear.

Also, air resistance increases with speed and this will cause greater fuel consumption.

Shibumi1

i had a pm.. sayin that the rpm level maybe higher @ 88mph.. i chk'd today its exactly 2300rpm on my car, 90mph is almost 2500.. if that is constant.. then u really wont burn much fuel.. but if ur at 50 then gun it to 88 of course its gonna affect the mileage.. ask yourself why is city mph always lower than highway.. its the stop an go that burns more fuel.. highway "should" be more of a constant bcuz there's a greater span of time between stops..

Silverpaws

Yep!

TJW98LS

iTrader: (1)

Do as the manufacturer asks. I'd rock premium in the oldest, most rundown LS400 I could find.

Hilux22RE

+1

TJW98LS

iTrader: (1)

200 RPM in highway cruising is significant... By about a MPG or so. at 100 MPH in the LS430 (2800) RPM I get about 23-24 MPG but when I settle down at 70MPH (2300RPM) I will get a consistent 27MPG.

I mean, what are you really gaining when saving the money? $6.00 per tank (.30 Cents/Gal difference x 20 Gallons), minus the additional gallon it shaves off of your mpg HIGHWAY ($4.00) on average, so if we consider only highway driving, because city driving you would end up using much more fuel to start the car from 0mph, you would net probably $2.00 a tank, at the expense of the engine life...

USLEX

Unless you are a race car driver wanting to squeeze out every ounce of horse-power out of your engine, Regular is fine. I have a LS600h and have ran it on Regular from day 1. No problems in power or nocking. I have a friend that is a petroleoum engineer (chemical engineer) and he he says he runs Regular on his premium vehicles and his kids non-premium vehicles. That said, you do lose some horsepower 5 or so for this engine but nothing you will notice.

stevechod

just curious. what's the worst MPG on a tank someone has seen?

vancouverl

After all the research and comments using premium will give the extra horse power stated by manufacturer .It will not prolong the life or operation of the engine .regular will work just fine and cause no damage whatsoever. Lexus sells and has dealerships in other countries that do not have 91 octane .in those places regular unleaded is recommended .there is no modifications done to the engine .

Pushkar

so whats the final word on what gas to use in the LS460? Knowing myself, i will probably switch off according to my mood. In the past i have heard that's the bright line rule on what NOT to do. Please chime in ...

Tee

Sorry…..your LS460 is a Premium car that runs on Premium fuel (Go figure) to perform how the engineers designed it too. We are driving a ‘FLAGSHIP’ car that the owner’s manual & plastered on the gas door to use Premium only, but guys want to put regular in it like it’s a entry level car??! It’s like having champagne taste on a Old Milwaukee beer budget, it is like complaining about how much the maintenance is (on this level of a car) compared to a lesser one.

Why are some surprised?

Did anyone do their homework before they bought the car or research what their annual ownership cost would be?

Life is full of curve ***** and higher gas prices is one of them, yes it SUCKS! Owning a car that runs on premium when gas goes up is part of the territory, it is what it is.

CJITTY

I know some folks who fill up with 93..then drive for awhile and fill up again at half tank with 89 to average out 91 octane.. seems to me if you have a car with MSRP up past $75k, you can handle putting mfn premium gas in it..smh

brianlin87

iTrader: (11)

It's as simple as just putting 91/93 whatever the highest octane gas available is in your car.

Trying to get creative with it, is just asking for trouble.