Gas prices have me wondering if 89 octane will be okay in high mileage LS400,
I've put in a few gallons recently and noticed no adverse changes. I just filled up back with 93 octane as I wasn't sure if a 95 LS has a low octane table for lower grade gasoline.

 

puredrifter.... where are you?

 

Do an advance search under LS400 forums for: lower octane and you will get a wealth of info.

 

Ha ha I was wondering the same thing about Pure. There are many threads here on this topic. Short answer for me - 89 will work but it is not worth the few bucks you'll save. I'd rather cut back on a lunch or something.

 

That PD must be snoozing. Finals is no excuse...priorities for the Lexus brethern.

Try it. I did the 87, 89 and 91. My conclusion 91 gives me the performance and mileage. Trying to save $3.00 per tank on 87 octane or $1.50 at 89 Octane (based on a 15 gallon fill) is . Now if one is tanking up every couple days, the LS is not the car for such commutes.

Another way...what you think you save is relative...lower octane gave me lower MPG so I was back filling up sooner. Not to mention, the car retards timing for the lower octane gas...some may not notice but mine didn't pick-up as well.

YMMV.

 

Pardon my tardiness guys

OP:search....

or else....

 

yeah, guess not worth it.
I just hated the fact I have to pay 4bux a gallon and was trying to avoid it as long as possible. I have a turbo Camaro that's been sitting for a couple weeks, b/c I couldn't see me paying that much per gallon for gas. to keep myself out of shock, i put in 5 to 10 gallons at a time. gotta play mental games to keep sane in this crazy world.

 

a quick search revealed this: https://www.clublexus.com/forums/sho...ghlight=octane

haha, i'm a newbie and i even know how to search!

As in other automotive communities, a lot of it depends on your altitude, the compression ratio of your motor and it's timing.

Now, i'm not trying to beat a dead horse, but in the landcruiser world, the 1fzfe motor is a 9:1 compression motor. When running lower octane fuel at lower altitudes you will get some off idle pinging or pre-detonation. We simply retard the timing a degree or so and it fixes it.

I'm sure you could do the same in the LS??

 

5 hour delay...he needs the quick online reflexes like Rominl. Who can scan each and every forum within nano-seconds along with a 200+ word reply if necessary.

 

Haha....im another... busy on 6 or more forums at one time

 

i have SCHOOL man, gimme a break guys

education calls....

 

I've been going with the middle grade for a few months. It doesn't ping or knock. If it ever does I'll go back to Super, but so far it hasn't.

 

lol thats not ur mind talkin . im running 89 now but ive been doing the math and its just a couple more dollars.

 

HELLO PURE DRIFTER last week I ran 89 octane from Orange County to San
Diego and back running at 60mph on the freeway and I ran about 30% in town driving and got 24.6 MPG I also drove the whole trip easy on the gas and was suprised to find out that a 91 LS400 could get that may miles to the gallon. I recently changed to iridium plugs and this helped a little as you know I am a fan of all synthetic fluids and K&N air filter I feel all this helps in some way to get good mileage. YOUR THOUGHTS PURE DRIFTER

 

24.6??? That's it??

I got 27.8 in my 97 with 140k miles on a stretch home when I got it. That was with a horribly clogged air filter. dirty plugs. dino oil. horribly dirty throttle body, before I seafoamed, etc..

I bet I could have gotten closer to thirty, had it been maintained properly.

LS is designed to run on premium. if ran on regular you will loose mileage and performance. It's been well documented.