[PapaMurph]

I just purchased a 2013 Cruze 1LT. I immediately inflated the tires to 44psi. I topped off the tank before coming back with regular (87) - not knowing what the dealer had put in there. I got 38.5 mpg on the drive home according to DIC. Was over 40 mpg until the last hour or so. I had an anxious 5 year old with me - so I wasn't quite as obsessed with my mpg the last part of the drive. I was at 39 mpg on my commute this morning--including some stop and go.

The ride seemed fine to me with 44psi--especially compared to my old ride. I am really curious to see what mpg I get at the higher fuel grade. I know with winter coming, I may run into too many variables to isolate the difference--so interested in what others have seen.

Currently, there is about $.15 difference between each grade. Station closest to my office is at 3.09/3.24/3.41. I would need to see about a 5% increase in fuel economy to justify to midgrade, or 10% for premium. From what I have seen so far browsing the forums, that seems entirely possible, right?

Loving this forum--and loving the Cruze.

 

[spacedout]

I only see a 1MPG increase from midgrade to premium, however the car seemingly has a bit more power especially at low RPM with premium. I prefer how it feels with premium so I'm willing to pay a bit extra even if the cost per mile doesn't work in my favor. Here the average is 20 cents more for midgrade, 60 cents for premium.

My car will never get 87 octane again while I own it, low RPM(below boost) seems to have less power and if pulling out into traffic seems much more dangerous. At minimum I would run midgrade.

The DIC(drivers information center) is optimistic, so if your seeing 38mpg, that's probably only 34-35mpg pump calculated.

 

[PapaMurph]

I am going to fill up at Shell tomorrow with 93. The station closest to my office is the one with just the $.15 difference from midgrade and it is a very high volume station. I will be able to run the current tank pretty low and fill up in the morning. Sitting in the highway for an hour barely moving did not help my avg fuel economy, but I was able to get a pretty typical drive home yesterday at 40 mpg by the DIC, so I should be able to get a decent comparison in later this week.

 

[PapaMurph]

Filled up after my drive in. 36.6 mpg calculated for my first full tank. DIC showed 37.4. Not as much of a difference as I thought.

I may be learning how to drive even more efficiently. Despite more heavy traffic, I had my best DIC calculated efficiency at 42.8 this morning before filling up. Very interested in what difference I see from the premium gas.

 

[spacedout]

Filled up after my drive in. 36.6 mpg calculated for my first full tank. DIC showed 37.4. Not as much of a difference as I thought.

It will very from tank to tank how far off it reads, Mines usually between 1-4MPG high(around 8% optimistic on average). Example, my last 5 fillups pump calculated vs DIC:

Pump 37.36MPG DIC 40.8MPG = 3.4MPG high
Pump 38.98MPG DIC 42.5MPG = 3.5MPG high
Pump 41.22MPG DIC 44.7MPG = 3.5MPG high
Pump 41.37MPG DIC 43.3MPG = 1.9MPG high (85% highway)
Pump 36.97MPG DIC 40.4MPG = 3.4MPG high

I recommend setting up a fuelly.com account to keep track of your milage.

Very interested in what difference I see from the premium gas.

Make sure to run premium a few tanks before you make any judgements, seems the car needs some time adjust fully to the higher octane.

 

[PapaMurph]

Thanks. I did setup the fuelly account--apparently I did not set up my signature correctly to show it on my posts.

 

[spacedout]

Thanks. I did setup the fuelly account--apparently I did not set up my signature correctly to show it on my posts.

I beleive there is a thread that goes over this in better detail, but here is a quick run through that might help getting your signature setup.

Goto your fuelly page, the one that has all your fill up logs listed. Just below the logs in the lower left, is a link that says "badges". Click on that link. Once on the Badges page copy the text in the first box.

Return to Cruzetalk, Click on settings in the upper right, Then in the left column select edit signature. Paste the text you copied from Fuelly into the box then click the save signature button.

 

[PapaMurph]

looks like I figured it out. Thanks!

 

[sublime1996525]

It's yours an auto or manual?

 

[CruzeEcoBlueTopaz]

We almost have to factor in the fuel rate of flow at the pump when calculating our mpg. I mean if the pump flow rate is slow its possible for more fuel to be pumped in and cause a lower actual mpg. If the pump flow rate is fast it could result in less fuel accepted into the tank and an increase in actual mpg. Pump flow rates very from station to station and the settings on the nozzle. If possible, to get the most accurate mpg I would suggest fueling at the same stations and same nozzle flow rate. Im sure this is more of an issue for eco tanks.

With my eco I personally experienced this often at a station using the fastest nozzle flow rate, I would fill up and notice the needle not reaching full.

 

[PapaMurph]

It's yours an auto or manual?

Mine is an automatic. I've been getting great mpg on my commutes-lowest commute after my 2nd fill up is over 40 mpg on the DIC-best is 44 mpg.

Might go for a badge this week. If I only use this for my commutes and use the wife's car for short trips I may have a shot.

 

[Eastwood]

Glad you're enjoying your Cruze. They do have quite a lot to offer.

I have the same car as you - automatic. I try to keep my tires at 50 psi. I normally see a 2 - 3 mpg increase from 87 to 91 and then another 1 - 2 mpg from 91 to 93 depending on the 93ness of whichever 93 octane I get.

You can see my Fuelly log if you want to see how a similar setup to yours is performing from about December to July (I'm not with the car, unfortunately, until the end of next month and the grill covers were not ran over the course of a tank as I made them during warm weather and am saving them for the winter). Most of my miles are highway, but there is usually enough city on each tank to bring the average down.

 

[spacedout]

We almost have to factor in the fuel rate of flow at the pump when calculating our mpg.

I experienced this on my last two fill ups. First one was much lower pump calculated than I thought it should be, the DIC was also reading 6mpg high. Next fill up though pump calculated seemed much higher than I thought it should be & the DIC was only 2mpg high.

Seems that first fill up the pump did not kick off at the same point as my normal station & I got extra fuel.

 

[Eastwood]

I experienced this on my last two fill ups. First one was much lower pump calculated than I thought it should be, the DIC was also reading 6mpg high. Next fill up though pump calculated seemed much higher than I thought it should be & the DIC was only 2mpg high.

Seems that first fill up the pump did not kick off at the same point as my normal station & I got extra fuel.

Yep, definitely keep that in mind if you want consistent results. Same station, same pump.