1Louder

They went out of their way to tell me the same thing! Which I thought was very odd. This is a $48-50k (ish) car but they think a selling point is I can save 30 cents a gallon on the fuel...? First, I got the hybrid to get a lower gas bill and second, just seems like an out of place selling point for a luxury SUV. As if I was out shopping for a Highlander until the whole "regular gas" savings made the Lexus suddenly achievable.

Lexmus

In my area the difference between regular and premium gas is typically $0.60 per gallon. We average 22 MPG in our real world mix of city and highway driving. For 12000 miles of driving per year, that is 545 gallons of gas, resulting in a $327 savings for regular vs premium. Considering some of the cost savings ideas people post on the board, this is an easy way to save some real money with no negative impact. Assuming we would get 24 MPG with premium, that would still be $200/yr. Is regular gas the main reason why anyone buys an RX350? probably not, but it doesn't hurt.

dibl

$327 is about one-half of one percent of the cost of your $55K car.

GSFRX350

All in the name of better fuel consumption and to lower the running costs. You guys in North America are very keen to keep fuel costs down and to keep that sticker fuel consumption low. So they use regular for their fuel economy figures and the car works okay with regular. Here in Australia Lexus recommends mid-grade fuel, that's exactly what it says in the manual with no reference to other grades.
Is it common over there for manufacturers to say "or higher", it never matters if you use higher grades it's only when you use lower than recommended grades you may have driveability problems.

thehaviet

So we just did the math.

We will be driving around 10k miles per year, and let's say we'll average 20MPG. That means we'll need 500 gallons of gas.

Gas prices at our nearby Costco works out to about $0.24 cents difference between regular and premium. That's a difference of $120 for the ENTIRE YEAR (or $2.30 a week) if we were to use premium.

If premium gas give us even a slight increase in performance or efficiency, I think the choice is quite clear.

GSFRX350

Don't know about performance but it does improve the economy a little. I never bothered to work out the cost benefit ratio though.

exonw

I didn't really find much difference filling premium and doing my math based on past consumption with a difference of $0.25 ~ $0.28 per liter;

- Pre-Covid 2019: 2300ltrs Diff: C$575~C$644
- COVID-2020: 1600ltrs Diff: C$400~C$448

Planning to keep vehicle until end of extended warranty (Y'2025) and maybe a bit more so I'm sticking with Shell's regular (87) .

autotech13

I have been using mid grade with very good results. I find little difference between mid and prem grades.

Badhobz

you americans have it really good. the difference for us Canadians (here in BC) between regular and premium is outrageous. Regular is sitting at 1.48 a litre vs premium at 1.72. That's a difference of 24 cents per litre!!! a regular fill-up takes about 60L so that's 24cents x 60 = $14.40 per tank. lets say, 2 tanks a month = 30 dollar difference, x 12 = 360 bucks a year

That's not nothing, especially when there are negligible performance gains or benefits.

if your car doesn't require it, don't waste money filling it up with premium. Just burning money

ellocovg

iTrader: (1)

I'm in NJ and that’s kinda what the difference is here money wise as well a little more actually. For my old man story when I got my first car back in 1999 Amoco used to be 99¢ $1.09 and $1.19 then when gas spiked up around 2008 all of a sudden the difference from regular to premium became around 30 to 50¢. I personally use regular and every 4/5 fill up I run it down to about 1/8 of a tank and fill it with premium. I then top up with regular when I hit around the halfway mark the next 3/4 times. I don’t notice any difference in performance or sound at all. I do always use Exxon and avoid the generic gas stations which I don’t trust there premium to actually be premium or fresh gas for that matter.

QUOTE=Badhobz;11036962]you americans have it really good. the difference for us Canadians (here in BC) between regular and premium is outrageous. Regular is sitting at 1.48 a litre vs premium at 1.72. That's a difference of 24 cents per litre!!! a regular fill-up takes about 60L so that's 24cents x 60 = $14.40 per tank. lets say, 2 tanks a month = 30 dollar difference, x 12 = 360 bucks a year

That's not nothing, especially when there are negligible performance gains or benefits.

if your car doesn't require it, don't waste money filling it up with premium. Just burning money[/QUOTE]

Quantum501

Yeah, I switched over to Sunoco Evo 10 racing fuel. It is 105 Octane and costs about $9.45/gal. But I use about 500 gal/year for a total cost differential of like $3000/year. But that is only about 5% of the cost of my car, so seems like a good deal b/c now my SUV goes 0-60 in about 6.9 seconds.

bamalam

Ok, so that made me spit my beer. Thanks for the laugh!

plee82

Hey guys,

Just got a RX350 2021 with 4 miles in the ODO last week. I've been searching about the performance difference of using regular gas or premium gas. I do not care about the price per performance, or anything related to price. All I want to know is, does using premium improve the performance of the car? I have a MDX 2020 that takes premium. The manual on that car says Minimum 87, Recommended 91. The difference in acceleration is noticeable. The RX350 2021 manual just says "87 or higher". The compression ratio of the engine used in the MDX 2020 and RX350 are almost identical, 11.5 (MDX) vs 11.8 (RX350). This is why I am wondering if the gas makes any difference in this car. Thanks!

dibl

The answer is YES, a bit. 89 or 91 octane. Anything over 91 doesn't make any difference on mine. Try a 200 mile road trip on your 87 octane, and then do the same thing with a tank of Shell 89 or Costco 91, and check the gas mileage carefully both times. (It's great to be retired and take day trips whenever ....).

My personal theory is they've used the VVT-iW on the intake cam, plus the (software controlled) ignition timing, to de-tune an engine designed for higher octane to keep it from knocking on 87 octane. ie. Designed by Marketing. ;-)

plee82

Oh wow. Interesting. They should have just done what Acura did with their MDX. Minimum 87, Recommended 91 in the manual. If your theory is correct, does that mean this is not just a simple ECU that's retarding the timing (and performance like Acura) but an actual change in the parts to detune the engine?