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Discussion Starter · #1 ·
OK, we are up 1.8 MPG after the first oil change (using Mobil 1) and switching to Mid Grade Gas. I don't know which one (or if both) contributed to this, but am very happy!

For us it is less about the fact of saving money (as we are obviously paying more for the Mobil 1 and for the higher gas), than it is about using less fossil fuels.

I still feel guilty for not buying a Hybrid, but I couldn't find one I liked that seated 7! (LOVED the Lexus 400h-- but it only seats 5 :( )

Anyway-- we are at 17.7 mpg-- we have an AWD! Yeah!
 

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Is the 1.8 mpg increase an average? Over how many tanks of gas?
 

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Discussion Starter · #3 ·
That is tank average x2 tanks. We noticed it the FIRST tank after the oil change/gas grade change, and thought it might be a fluke, or due to more freeway miles that tank (which we didn't really think had occured, anyway). But after the second tank that showed the same numbers, we are convinced that the oil change/gas grade really did make a difference. We had the car 2 mos before the oil change and had put 3400 miles on it, so a reasonable number of tanks of gas (all the tanks averaged 15.5-15.9 MPG per tank)......then BAM! major difference in numbers.
 

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Great combo with Mobil 1 !!! the Acadia does recommend a mid-grade gas. :thumb:
 

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I would love to know what happens if you go back to 87 octane. From everything I have read, the mid-grade causes increased HP, and lower MPG. The mid-grade for sure will increase the performance, but the fact is that the mid grade does not have more power per gallon. It explodes at a higher pressure causing the engine to perform at a higher HP. This is should cause better performance and a lower MPG.

The Mobil 1 on the other hand should cause higher MPG due to less friction and the fact that it burns at a higher temp. This allows the oil to continue to seal the rings around the pistons farther up the stroke before burning off and allows for higher compression and more HP.

So my guess is that if you go back to regular gas, you will not see a reduction in MPG and that all of your improvement in MPG was due to the Mobil 1. That is just my guess, so if you do a test, please let us know what you find out.

I will be switching to Mobil 1 at 6000 miles at my next oil change. I hope to see improvement!! :)
 

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IMHO, the aditional octane allows the engine to run with more spark advance, thus giving you more power at all RPM levels. Therefore, it takes less throttle (i.e. less air/fuel) to do the same work. This assumes of course that the engine has detonation detection/auto timing advance, and adjusts to the higher octane fuel. Thought on this?
 

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i_like_f150s said:
IMHO, the aditional octane allows the engine to run with more spark advance, thus giving you more power at all RPM levels. Therefore, it takes less throttle (i.e. less air/fuel) to do the same work. This assumes of course that the engine has detonation detection/auto timing advance, and adjusts to the higher octane fuel. Thought on this?
All modern cars nowadays have the feature, its all in the car ECU, it will take them a while to adjust to changes in fuel octane but the performance is surely noticeable. Unless, its a manufacturer's recommended or your vehicle is boosted, theres no problem upgrading to the more combustible and cleaner premium fuel......

the only thing that would be hurting is your wallet!!! ;D
 

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SioXie said:
Great combo with Mobil 1 !!! the Acadia does recommend a mid-grade gas. :thumb:
No the recommended fuel is 87 unless detonation occurs. I believe the 89 might be required if pulling a trailer, but otherwise 87 is the one. Higher octane does not produce more hp in an engine that was designed for regular fuel. The higher octane just resists pinging or pre detonation more than regular octane.
 

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Could the mileage increases also be related to the vehicle maturing and the engine/tranny settling in after 3k miles?

Updated: I do agree with using Mobil 1 regardless just for anything but the peace of mind related to engine protection.
 

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big bear craig said:
No the recommended fuel is 87 unless detonation occurs. I believe the 89 might be required if pulling a trailer, but otherwise 87 is the one. Higher octane does not produce more hp in an engine that was designed for regular fuel.
Well put. Unless the engine can use the extra octane, it's a waste. More octane = more power (in an engine designed to use it.) ;D

On an octane related note, I saw the Horsepower episode where this product was dyno tested:

http://www.fitchfuelcatalyst.com/products/auto/index.html
 

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I believe the increase in MPG is entirely due to M1. I have an 08 AWD SLT2 and switched to M1 at around 2.5K, it's got over 5K now, and I average 18.7MPG consistently. Pure freeway driving I can consistently get 20.4 to over 21MPG, don't think I have ever gotten the 22MPG as stated by the EPA estimate. But with the M1 at least I can get pretty close using only 87 octane, still waiting to see what kind of fuel economy I will get on a long road trip, freeway driving in the NYC area isn't exactly smooth.

Mike
 

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mikehw17 - do you have AWD or FWD?

thanks
 

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I've recently changed the oil in the Acadia too with about a 1-1.5mpg average increase. HOWEVER, I used regular dino Valvoline 5w-30. I'm now getting upper 18's-lower 19's. Just some food for thought.......And by the way, I have used Mobil 1 and have nothing against it, but I believe the mileage increase is attributed to these motors constantly breaking in plus having fresh, slippery lubricant. :eek:
 

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What were the results of the horspower episode of the fitch fuel catalyst. I have a friend that installed this on his boiler at home and they did show a reduction in the exhaust temperature leaving I believe is what he told me.
 

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Just curious...when you talk about Mobile 1, are you talking about synthetic, Mobil Clean 5000 5W-30, Mobil Clean 7500 5W-30 or other?
 

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big bear craig said:
SioXie said:
Great combo with Mobil 1 !!! the Acadia does recommend a mid-grade gas. :thumb:
No the recommended fuel is 87 unless detonation occurs. I believe the 89 might be required if pulling a trailer, but otherwise 87 is the one. Higher octane does not produce more hp in an engine that was designed for regular fuel. The higher octane just resists pinging or pre detonation more than regular octane.
try using regular fuel for 2 months then shift to premium, im sure you will notice the difference. pre-detonation occurs only when you are using regular fuel on a boosted engine i,e. turbocharged, on which case is not applicable to the Acadia.87 octane is just the starting fuel but 89 octane is recommended for better performance wheter your towing or not.

SEL said:
Could the mileage increases also be related to the vehicle maturing and the engine/tranny settling in after 3k miles?
yes!
 

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JasonM said:
What were the results of the horspower episode of the fitch fuel catalyst. I have a friend that installed this on his boiler at home and they did show a reduction in the exhaust temperature leaving I believe is what he told me.
I can't recall exactly, but seems like the engine (a late-model GM crate engine, injected, LS6 or LS9 maybe??) made the same power on 87 octane + catalyst as it did with 92. The episode aired within the last six months or so, but now that they are on a new season, not sure when it will air again.
 

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SioXie said:
pre-detonation occurs only when you are using regular fuel on a boosted engine i,e. turbocharged, on which case is not applicable to the Acadia.
I thought that high compression or carbon deposits, which can cause hot spots, can also cause pre-ignition.
 
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