What Type Of Gas do you Use?

[rumdada]

I have the 4 cylinder lacrosse and I am averaging around 19mpg higway & city combined. I use the cheapest Gas does that make a diffrence on the MPG ? should i use the more expensive gas? Side note i just got my lacrosse it only has 300miles on it

 

[pogster]

What do you mean by cheap? As in poor quality? As far as octane goes use what's recommended in the manual.

 

[rumdada]

Cheap = 87

 

[Buick Customer Service]

Rumdada, the following information is from your owner’s manual:

Recommended Fuel
If the vehicle has a 2.4L L4 engine
(VIN Code C), use regular unleaded
gasoline with a posted octane rating
of 87 or higher. If the octane rating
is less than 87, an audible knocking
noise, commonly referred to as
spark knock, might be heard when
driving. If this occurs, use a
gasoline rated at 87 octane or
higher as soon as possible. If heavy
knocking is heard when using
gasoline rated at 87 octane or
higher, the engine needs service.

If the vehicle has the 3.6L V6 engine
(VIN Code D), use premium
unleaded gasoline with a posted
octane rating of 91 or higher. You
can also use regular unleaded
gasoline rated at 87 octane or
higher, but the vehicle's acceleration
could be slightly reduced, and a
slight audible knocking noise,
commonly referred to as spark
knock, might be heard. If the octane
is less than 87, a heavy knocking
noise might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. Otherwise, you could
damage the engine. If heavy
knocking is heard when using
gasoline rated at 87 octane or
higher, the engine needs service

Thanks,
Laura
Buick Customer Service

 

[Cman50]

It doesn't make sense to spend good money on a vehicle only to get cheap when it comes to putting gas in it. At a minimum, I use 89 octane and even then, I'm careful where I buy it.

 

[cheflionfoot]

I only use premium. Then again, my engine is the V6

 

[Thehatguy]

89.

This car doesn't need premium.

 

[pogster]

89.

This car doesn't need premium.

That's the difference between recommended and required.

 

[thalter]

19 is pretty poor for a 4 cylinder. I have the six and I average 20 in mixed highway and city, and I drive pretty aggressively (80 mph freeway).

 

[vid53]

I use reg. unleaded on my 3.6 and it runs fine.

 

[cheflionfoot]

19 is pretty poor for a 4 cylinder. I have the six and I average 20 in mixed highway and city, and I drive pretty aggressively (80 mph freeway).

I agree. I average 22 mpg on my 3.6L.

 

[rumdada]

I agree. I average 22 mpg on my 3.6L.

Do you guys think its because the car hasnt really yet been broken in?? i have 402 mi on it right now.

 

[pogster]

I use reg. unleaded on my 3.6 and it runs fine.

No engine knock under load or hard acceleration on hot days?

 

[cheflionfoot]

Do you guys think its because the car hasnt really yet been broken in?? i have 402 mi on it right now.

Do you do a lot of city driving, sitting in traffic?

 

[cheflionfoot]

I use reg. unleaded on my 3.6 and it runs fine.

My car was delivered with a full tank of regular and the engine had a knock. Every subsequent fill up I have used premium, and after two fill ups, the knock went away and the performance increased a lot.

 

[Fulkem]

I have a 2010 CXS 3.6 and I use premium. I do a lot of driving, mostly highway and average about 22mpg...mine is already broke in at 39k miles

 

[vid53]

I am also avg 22 mpg with reg. mostly highway driving. Not what i expected, very disappointing.

 

[Cman50]

I'm getting 27-28 mpg hwy using 91-93 oct. I try not to average more than 70mph and use cruise control whenever possible for steady fuel consumption.

 

[rumdada]

Do you do a lot of city driving, sitting in traffic?

I have a good mix but yea i live in pittsburgh and hit rush hour traffic daily, i just filled up with 89 and idk but im getting 20mpg hwy/city right now not a big diference

 

[taverg03]

19 is pretty poor for a 4 cylinder. I have the six and I average 20 in mixed highway and city, and I drive pretty aggressively (80 mph freeway).

Ditto for an '11 CXS but not that aggressive a driver (usually 70-75 max on freeways). I average about 20.5 for 60/40 'burb'/highway with average speed for that about 30-31 mph per DIC. Average speed is a main determining variable with these heavy beasts. On highway driving I average 27-28 mpg at about 60 mph average speed. I use top brand 87 octane since I had no knock and only minor mileage difference with 89 or 91.

Prior Buick:'78 Electra