1995LS400

Early next month Im driving to Colorado Springs with my sister and her 2 kids to go see my brother (military). The trip 1 way is around 475 miles. Now Im not paying for the gas, she is. I dont want to rip her off by saying that I have to put 91 in, even though 91 is what Ive used since the day I bought the car.

Ive heard you guys saying something about "pre-ignition" with lower octane, but I will just be using the fuel for highway travel the whole time.....no gunning it. Do you see any problem with just this 1 time in the cars' life that it will be burning the "cheap" stuff.

Kaydee

best thing I would do is to just use 91 and pay 50/50...don't take chances

PureDrifter

iTrader: (10)

meh, i run 89 from time to time and it doesnt make much difference if you drive with a light foot anyways.

19psi

i would run the premium. i always run premium and i woudlnt' consider it ripping anyone off if that's what youalways do. now, if you never run it but decide you want to run it on the trip just because you're not paying for it, then maybe.

LEX012006

Had a 97 ls and ran 87 octane for about 60,000 miles and never had any pre-ignition issues. Most of my driving was highway though (100 miles a day) also drove south several times and vehicle ran perfect. No problems at all.

Now my 01 UL, I would have to admit I use the recommend grade (91 octane) but on a few occasions have use 87. And once again there was no issues when I ran 87.

Now in the owners manual, they state that you can use 87 octane for a short time, if 91 octane is not available!!!!

cjmeyer

I use 87 on my 95 LS and it runs fine.Accelaration is not as strong but saving 30 cents a gallon is adding up.

1995LS400

That's the 10% ethanol stuff right?

steveski

True - good point as the manual states using lower grade gasoline is fine for a short period of time.

sonyman

No, that's the regular stuff. However, in many parts of the country all 3 grades contain up to 10% ethanol. I remember when it used to be labeled as gasohol years ago. Now they just sneak it in.

jcrome04

You'll get worse mileage with 87.

You're not ripping off her you're ripping off your car.

You should be able to go +500miles on a full tank highway

denverdog

i live in denver and have run midgrade (87!) for years. no knocking whatsoever. mileage is about the same. i do not drive the car hard. octane is lower here because the air is thinner and compression of the mixture is less. and colo spgs is a thousand feet higher than denver. life is better when you're high all the time.

i suggest you take your relatives to the broadmoor for sunday brunch. it is the best value in colorado.

GSteg

iTrader: (15)

A full tank of 91 will only cost $4.00 more over regular. Assuming you need 2 tanks to make a full trip, that's $8 difference......

Offer to pay the difference between premium and regular.

Mugen_1

The users manual for the '97 LS400 recommends 91, but says that 89 with 10% ethanol is fine.

And where I live, the 89 is about 10 cents per gallon cheaper than the 87.

When I first got it, I was hesitant to put anything low grade in it, so I filled it up with Shell V-Power...then I read the manual and have been using 89 ever since and average about 20.7 mpg driving about 20 miles highway back and forth each day to college.

docdgt@com

I have been using 87 exclusively for well over a year with no adverse effects at all. The performance "seems" the same, but if measured it might be a bit less. As to mileage, I get around 19-21 mpg in town and 24-27 on a highway trip with 87 octane. I have a light foot and my car is a '97 Gen II.

I'd say give it a good try and see what you think; I don't believe you will hurt your car one teeny bit.

GKLCPA

I've been using 87 since gas prices went up with no ill effect. I plan to continue as long as gas remains at stratospheric levels.