What type of gas does the GXP take??
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From: Upstate New York
What type of gas does the GXP take??
I'm pretty sure that the newest Caddy Northstars run on recommended 87 octane,...is that the same gas that the new GXP'* are recommended to run??
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compression was dropped from 10.3 to 10, and the combustion chamber was redeisned so its made to run off 87, id still use 89/90 since a few places charge the same for 90 as 87 (there'* a place in mn if anyone wants to know about it off cedar)
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From: Purgatory
Copied from the 2004 Bonneville owners manual.
Gasoline Octane
If your vehicle has the 3.8L V6 engine, use regular unleaded gasoline with a posted octane of 87 or higher. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine. A little pinging noise when you accelerate or drive uphill is considered normal. This does not indicate a problem exists or that a higher-octane fuel is necessary. If you are using 87 octane or higher-octane fuel and hear heavy knocking, your engine needs service.
If your vehicle has the 4.6L V8 engine, use regular unleaded gasoline with a posted octane of 87 or higher. However, for best performance, you may wish to use middle grade or premium unleaded gasoline. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
If your vehicle has the 3.8L V6 engine, use regular unleaded gasoline with a posted octane of 87 or higher. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine. A little pinging noise when you accelerate or drive uphill is considered normal. This does not indicate a problem exists or that a higher-octane fuel is necessary. If you are using 87 octane or higher-octane fuel and hear heavy knocking, your engine needs service.
If your vehicle has the 4.6L V8 engine, use regular unleaded gasoline with a posted octane of 87 or higher. However, for best performance, you may wish to use middle grade or premium unleaded gasoline. If the octane is less than 87, you may get a heavy knocking noise when you drive. If this occurs, use a gasoline rated at 87 octane or higher as soon as possible. Otherwise, you might damage your engine.
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From: Severna Park, Maryland US
theres this one sunoco gas station near my school that actually offers "Race Fuel" (yes thats what it says on the pump) 95 octane rating it was like 3.79$ a gallon last time i checked in like May hehe thats some rocket fuel! 
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our race fuel is 110 octane, last year it was about $3.50-4.00, not sure what its at now, probably more
running too high of octane can be just as bad as too low of octane. if a car is designed for 87, and you always put 93 in, it may have a problem actually igniting that gas, running 93 in a gxp isn't a problem because it still has a high compression, but im sure anything past 90 (midgrade) is overkill
running too high of octane can be just as bad as too low of octane. if a car is designed for 87, and you always put 93 in, it may have a problem actually igniting that gas, running 93 in a gxp isn't a problem because it still has a high compression, but im sure anything past 90 (midgrade) is overkill