Havn't noticed any difference between using 87 and 89 milage wise.

 

Little more than a few bucks here. I wish it was only $3.00 more, it's running me close to $10 more for 89.

 

Ouch... yeah, I guess that does make a difference. Sounds like I've been getting a little spoiled....

 

the graduated scale here (TN) is, .10-12 between 87-89 and .15-18 between 89-93. Sounds like a little price gouging going on is some places.

 

It is a .30-.35/gallon premium for 89 up here as well so I have used 87 99% of the time and no problems over 22,000 miles. I haven't noticed any significant power or mileage differences with 87 vs 89 vs 91 when I have ran a few tank fulls thru to check.

 

I find 89 octane gives me worse performance then 87 here in Toronto. Tried it a few times now (Shell and ESSO)... already have 21k on the 2009 Laramie, so I'm stay with 87. Haven't tried 91... but the manual said it's useless, any comments on 91 octane?

 

I have never had a full tank of either, so I cannot say for sure anything about mileage or performance. I fill mine up every time I am in town. It's never been below 1/2 tank.

 

This is my conclusion as of lately. I'll do one more tank, making 3 tanks total of 89 before I make a final decision to switch back to 87.

 

It comes up every time there's a topic on Octane ratings, but I'll reiterate that octane rateings have no effect on MPG what so ever. If anything using too high of an octane rated fuel than the computer can compensate for can cause a decrease in mileage, but there is probably larger variences in mileage calculations than this.

Right now at the corner Chevron its:

$2.69.9 Reg 87
$2.89.9 Mid 89
$2.99.9 Pre 93

Say you pump 28 Gal (low gas light on, some gas left in reserve on the 36 Gal tank)

Tank of Reg will cost you: $75.57
Tank of Mid will cost you: $81.17
Tank of Pre will cost you: $83.97

Now to me, $5.60 isn't worth 2 octane points. And I would rather buy top tier gas, than any grade at stations not meeting such requirements. Just because it says premium, doesn't mean its higher quality, don't give into the marketing hype.

 

I compared a couple tanks of 87 vs 89.I got another 1 mile per gallon with 89,did'nt notice a performance increase though.I looked at the savings of 87 vs 89 and I broke even,so I went with 87.Just my 2 cents.