GAS

Just about a year ago I started out on an 8month-8,000 trip around the USA with a 2011 Silverado-5.3 motor towing a 5,500pound-29 foot travel trailer.

I used the cheapest gas I could find, sometimes it was "name brand", sometimes not. I don't need to tell you that I used many, many gallons.

I had ZERO ISSUES with truck and trailer.

I've seen the difference in price between regular and premium gas as little as a dime and as much as 70 cents. If your vehicle performs better on premium, the difference may warant the extra dime but not an extra 70 cents. If your vehicle performs equally with both, premium is a waste no matter how low the price difference. If your vehicle only performs correctly on premium gas, any price difference is irrelivant. My TV burns diesel which has 13% more BTUs per gallon than any grade of gas, so the entire discussion is irrelivant for me.

Volkov wrote:

fla-gypsy wrote:
We have a few believers, keep on paying more and believing. The BTU content is identical.

Actually your theory is correct, but the reality can differ depending where you are and what regulations hold. Premium gas is often offered without any ethanol (where permitted)versus 5-10% ethanol in the standard grade. Given that ethanol has a significantly lower BTU content, they are not the same. If regular has 10% ethanol and Premium has none, you will get a 4-5% improvement in mileage.
The all gas to all gas Octane shouldn't make any difference IF the vehicle is properly tuned. If not and predetonation is happening, modern vehicles will pull timing and reduce the fuel efficiency. There again, preventing pre-detonation means better FE for premium.
94 at my local Chevron, "contains no ethanol". "up to 10% ethanol" on the other pumps.

I agree that "No Ethanol" is a game changer. That varies by location and has nothing to do with the octane rating.

dreeder wrote:
I just fill the truck where the best prices are, around here its Safeway and Western.

Same here, usually Arco in my area.

fla-gypsy wrote:
We have a few believers, keep on paying more and believing. The BTU content is identical.

Actually your theory is correct, but the reality can differ depending where you are and what regulations hold. Premium gas is often offered without any ethanol (where permitted)versus 5-10% ethanol in the standard grade. Given that ethanol has a significantly lower BTU content, they are not the same. If regular has 10% ethanol and Premium has none, you will get a 4-5% improvement in mileage.
The all gas to all gas Octane shouldn't make any difference IF the vehicle is properly tuned. If not and predetonation is happening, modern vehicles will pull timing and reduce the fuel efficiency. There again, preventing pre-detonation means better FE for premium.
94 at my local Chevron, "contains no ethanol". "up to 10% ethanol" on the other pumps.

The Texan wrote:

fla-gypsy wrote:
Here we go again! Premium fuel does not deliver better MPG, it resists early detonation as in less volatility.

Maybe for you it doesn't, but in my truck, it will increase mileage by at least 2 to 3 mpg........Have tried it several times and the results are ALWAYS the same.

The 6.2 in your 2011 Silverado is set up to increase HP with premium fuel (changes the spark timing). You will definitely see more power with higher octane and apparently better mileage in your case. My 5.3 does not have that feature.
ArizAl

PaulJ2 wrote:
Engines don't compensate for the fuel octane per say. It just listens for "pinging" and retards the timing if necessary.

True and in doing so they are compensating for a lower octane and you can never know it other than possibly notice a slight drop in power and mileage.

wilber1 wrote:
Used to be that if the engine didn't knock there was no point in using a higher octane. Not so clear anymore when engines can adjust timing to compensate for the octane of the fuel being used. In some cases using premium might get you better mileage, even though the engine will run fine on mid grade.

I can't hear a ping but mine will surge as it adjusts timing under hard acceleration. It doesn't do this with BP gas. 89 seems to give it a tad better mileage but I haven't given it a duplicate run on both 87 and 89. Probably due to less timing adjustments with 89.

Gas is gas is like saying all tires are the same because they're all made of rubber.

Engines don't compensate for the fuel octane per say. It just listens for "pinging" and retards the timing if necessary.

I had never heard of top tier. Thanks to the OP for bringing this up.