Premium gas for a 100

[bunduguy]

I'd like some input please. As the sticker told me to, I've been using only Premium gas on my '98 LC100. Question is, how important is it? I have noticed no difference in mileage/consumption. I know all the stuff about cleaner burning and deposits etc. ...., but on a vehicle this age (98 with 120k), should I be that concerned, or should I be MORE concerned BECAUSE of the age, and what are the pro's/con's that other people have found.

As a temporary resident of South Carolina for the next few weeks,
Thanks y'all!

 

[CSG]

I think the manual for my '02 Lexus Hundy says 87 but at our elevation 85 is the standard regular. That's what I use. I bought it used (one previous owner) at 68k and have put a couple thousand miles on it so far. Don't know what the previous owner used but it runs fine on regular.

I'm no mechanic so take this with a grain of salt but I think the main reason some vehicles suggest premium is more for potentially enhanced performance. I used to have a Miata that said to use premium. I did for a while and then tried a couple tanks of 85. Saw absolutely no difference other than saving 20 cents a gallon so used regular from then on.

 

[2000UZJ]

mid grade is fine, i wouldn't put regular in it. Mine doesn't like it @ 3K feet.

 

[CSG]

I live at 4500' ASL and 85 octane is just dandy in mine. The higher the elevation, the lower the octane needed.

 

[Sawyer]

been running regular on my 2000 for years. at sea level or in the mountains of Tahoe..... no issues.

 

[Jeep or Tacoma]

regular gas

I had a 98 fj 100 I sold it after about 125k miles but always ran regular except when I was headed to the mountains I don't think it is a big deal I never had any problems

 

[CA-RJ]

Man, you're talking about .20 more cents a gallon! That's $2.00 for every 10 gallons you buy. Is that really a huge concern for you? If the motor was designed to be run on 91, do it. Call me crazy, but if you can't afford to run premium in your LC, you shouldn't have bought it.

 

[Skidoo]

Over on IH8MUD 100 forum common thinking is you can run less than prem, but gas mileage is less so no cost savings. Computer retunes to run lower octane.

 

[bunduguy]

Man, you're talking about .20 more cents a gallon! That's $2.00 for every 10 gallons you buy. Is that really a huge concern for you? If the motor was designed to be run on 91, do it. Call me crazy, but if you can't afford to run premium in your LC, you shouldn't have bought it.

Dude, you seem to have missed the point. It's not about affording it; but thanks very much for your concern.

Just asked a question as a point of interest to see what everyone else is doing. If you can't make a decent comment, go start your own thread you actually have an interest in.

Everyone else... thanks for the interesting points. I have heard from people with other makes that different grades will not cause any damage or make any noticeable difference. Living at 7500ft in Santa Fe, what's the consensus; higher or lower octane for better performance?

 

[bunduguy]

Over on IH8MUD 100 forum common thinking is you can run less than prem, but gas mileage is less so no cost savings. Computer retunes to run lower octane.

thanks Skidoo,
That's what I was looking for. I didn't know that the computer retunes!

 

[CSG]

As I recall from a few Mud threads the consensus was that MPG were actually better on most models with regular instead of premium.

And, like I said, the higher the elevation, the lower the octane needed. That's why regular in these parts is 85 and not 87. We also get real gas, not a blend (which does affect MPG).

I've been averaging almost 16 MPG in my LX which is right at the top of the 13-16 guesstimate on the window sticker. Then again, some model years do suggest premium. In 2002 regular was recommended. I've also asked both the Toyo and Lexus service departments what they recommended and both unhesitatingly said regular.

On the boneheaded comment about how it's only x more and if you can't afford it, blah, blah, blah, someone always chimes in with that remark in these types of threads. You'll see it in every vehicle forum. I wonder if it's the same guy going from forum to forum?

 

[ginericLC]

I run the cheap swill in my 99. It isn't a problem at all. I don't have any issues and I've been doing it for over 40k. I've experimented with different octanes and not found that it increases power or mileage. If you want to get better mileage drive 55 mph and drive at sea level. I was pulling a little utility trailer in California a few weeks ago and got 19.5 uncorrected for 295s. At home I'm in the low to mid teens but I drive a lot faster and we are at almost 4k feet. At our elevation we don't have any real "premium" fuel. 2 octane isn't much of a boost.

 

[spressomon]

In a normally aspirated engine octane is directly linked to the elevation of operation: Just ask any sharp pilot. Its a waste of money to run premium if its operated at altitude. I don't have the exact minimum altitude/elevation but surmise based upon my testing its somewhere near 4,000' or so where higher octane just doesn't make a difference in performance in a normally aspirated engine.

Turbo or supercharge then throw that out the window...:coffeedrink:

 

[kjp1969]

Our '04 Sequoia has the 4.7 iforce engine (the same as your LC?) and I have never run anything but 87 octane. It lives at sea level, but has pulled our 6000lb travel trailer up to 9000ft on regular unleaded. It has around 72k on it right now.

I'm pretty sure that the only adjustment that the ECU would make is to advance the timing if more octane were available to do so safely. This might increase torque slightly, which could affect MPG reported by others.

 

[Redline]

For my 4.7L (in a '06 4Runner) I believe the owner's manual says for "maximum performance" run premium, leading one to believe that if you are okay with slightly? reduced performance that Regular would be fine. Since new I have intentionally run only Regular gas and the car performs very well.