GS300: Premium vs. mid-grade unleaded - Toyota Nation Forum : Toyota Car and Truck Forums

***humanoid*** · 07-19-2008, 06:32 PM

I'm in the process of acquiring a 1998 GS300 in very good condition. I'm pretty sure it takes premium unleaded as did our old '93 GS. The question is can we get away with using mid-grade (89 octane) rather than the super unleaded?

Oigen · 07-26-2008, 12:13 PM

As long as it's unleaded, you shouldn't have a problem. I know I haven't had, but on a different brand of car.

Derry · 09-03-2008, 03:53 PM

ran a Beamer, an S500 and now my LX430 on regular,, many thousands of miles an nary an issue,, guess if you want the max HP then ya need the high test,,

was a length discussion over on the Lexus forum about this subject and many JUST know they need premium fuel or their car will not run,, poo on that,, the oil companies love ya for buying it,,

http://www.clublexus.com/forums/foru...ysprune=&f=158

Derry

***new echo owner*** · 09-03-2008, 04:05 PM

You can probably do it, but the best answer to your question would be in finding out how does the car perform with either one. You can always run a couple tankful of medium grade fuel for one tankful of super just to keep everything nice and clean and working together.

N.E.O.

Derry · 09-03-2008, 04:26 PM

have always ran a good valve and injector cleaner in all my cars about three times a year,,

have tried the premium a few times in every car I have owned and really could not tell any difference and the MPG remained the same,, just not a hot rodder so guess if I was running on the track I could tell,,

Derry

meterme · 09-05-2008, 11:08 PM

if you're not jamming the accelerator down, you can use even lower octane gasoline. just know you have to drive more conservatively and really make sure you keep up with maintenance.

o2k · 09-18-2008, 04:03 AM

i run mid grade every once in a while.. Not a problem... But I cant feel a lack of power compared to premium. So I put it in the long trips.

djspawn00 · 10-28-2008, 01:16 AM

I run premium (93 octane) simply because I do get better mpg on premium vs other grades... you'll be fine on 89 octane as well since the ecu will retard timing slightly...

allicedout · 12-25-2008, 05:10 PM

Quote:

Originally Posted by djspawn00

I run premium (93 octane) simply because I do get better mpg on premium vs other grades... you'll be fine on 89 octane as well since the ecu will retard timing slightly...

I have to agree, Lexus engineered the car around premium fuel, you will get the best performance and optimum mpg using premium.