Chevrolet Cruze Forums banner
1 - 15 of 15 Posts

·
Registered
Joined
·
60 Posts
Discussion Starter · #1 · (Edited)
I have had my stock '12 cruze LT2 - Auto for about 3 weeks now. (1,600 miles so far - now 10,600 on the car total). Only change to the car has been to set the spark plug gap at 0.035. Nothing else has been changed. I am currently running 89octane gas.

Usage is my 85 mile per day (total round trip) commute to work:

about 30% 2 lane backroads (avg 56mph on cruze),
55% 4-lane (56mph - on cruze),
15% 35mph - city driving, usually on cruze)


I almost always drive on cruise when above 25mph. (accelerate, decelerate and run set speed on cruise, use brakes when I need to slow down more quickly) Usually travel at speed limit or one over. (with the slower flow of traffic)

I am getting very good gas mileage in the city (typically in the lower 30's.) Issue is when running on the highway at 66mph with the cruise on, I seem to max out at about 34-35mph.

My question is - what, if anything, can I do to get to the advertised 38mpg, I would love to hit the 40+ everyone else seems to be getting.....

Any thoughts?

Thank you,

Michael


Edit - my fuelly sig did not show up for some reason.... here is the page though - http://www.fuelly.com/driver/mcloki/cruze

if you look at the notes, I list what the DIC showed each fill up as well.
 

·
Premium Member
Joined
·
5,157 Posts
What is your highway route like, and are you constantly passing folks? If it's hilly and you're passing folks on the uphill parts, gas mileage tends to be worse. A 56 mph average speed says that you're either always on the highway, or are doing a lot of spirited driving. With mostly highway miles on my Cruze and 55-60 mph speeds, I see a 40-43 mph average for the tank. Even setting the cruise control at 62 mph highway I'll only see 48-50 mph average speeds for the tank. Averaging 56 mph for the whole tank says to me that you're spending a lot of time at higher speeds than 66 mph.

I'd try being a right-lane hog, and try not to disengage cruise control for anything.
 

·
Premium Member
Joined
·
25,595 Posts
Try this a few times in both directions. Once you're at cruising speed, reset trip 2 and when you're ready to slow down, check the average MPG at that point. Do this in both directions for a few days and let us know what average speed and MPG you're seeing. Also, put your car into M6 as that seems to help the automatics coast better when going downhill. Do you have any hills in your route that cause the car to downshift? Also inflate your tires to 40 PSI (I believe 44 is the max sidewall) and use your A/C instead of rolling down your windows. On the highway the A/C is more efficient than the windows down. Also, if you have a sunroof, close it.

To get into the 40s on your commute is going to be hard, but you should be able to get closer to the 38 MPG highway than you appear to be getting.
 

·
Premium Member
Joined
·
25,595 Posts
I just saw sciphi's response - he and I have the 2012 ECO MTs, which is the only Cruze trim rated above 40 MPG highway. One more thought - try 91 or 93 octane. There is a noticeable improvement for most Cruzen with the higher octane. If you see improvement on premium the question you'll need to ask yourself is "is my cost/mile lower even though I pay more at the pump?"
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #5 ·
Replies are in-line.... and red

What is your highway route like, and are you constantly passing folks?
highway route is about 10-15 miles with 4 stop signs and 1 stop light - all very light traffic and a 55mph speed limit. (welcome to the mid-west) I always drive with the cruise on and about 1 mph over the limit so I almost never pass anyone. (I do get passed fairly often though)

The expressway part of the trip has a few hills and long gradual inclines or declines (depending on direction travelling) None are enough to drop the auto out of 6th gear (MPG on the larger hills is about 27-30 going up and 99 going down, the more gradual slopes are 32-33 going up and 44-45 going down)

. Averaging 56 mph for the whole tank says to me that you're spending a lot of time at higher speeds than 66 mph.

The fill up where I was averaging 56mph for the whole trip was almost all expressway mileage (incorrectly listed as highway in my notes) for a trip my wife and I took to a horse fair. 217 miles each way. That tank was filled up friday, drove home from work, then drove the 217 miles up - 217 miles home - then filled up again. There was about 40 miles of that 217 (each way) that was 55mph highway. I get MUCH better mileage at 56 than I do at 66.

I'd try being a right-lane hog, and try not to disengage cruise control for anything.

Right there with you.
Try this a few times in both directions. Once you're at cruising speed, reset trip 2 and when you're ready to slow down, check the average MPG at that point. Do this in both directions for a few days and let us know what average speed and MPG you're seeing. Also, put your car into M6 as that seems to help the automatics coast better when going downhill. Do you have any hills in your route that cause the car to downshift? Also inflate your tires to 40 PSI (I believe 44 is the max sidewall) and use your A/C instead of rolling down your windows. On the highway the A/C is more efficient than the windows down. Also, if you have a sunroof, close it.
I was planning to use trip 1 for per tank averages and trip 2 for per oil change averages but since I plan to do my first oil change well ahead of schedule - I will play with the trip 2 and let you know what I find out.

never thought of the M6 trick. I will try it both ways a few times and let you know if makes any difference (I will include it in the notes from the trip 2 averages you suggested above)

tires are currently inflated to 42psi cold. (when running on my commute, they tend to warm up to about 45psi warm. (temps have been in the 50's and 60's here lately)

Due to temps, have not been using A/C yet (nor windows down - just using the vent) and no sunroof on the car.
I just saw sciphi's response - he and I have the 2012 ECO MTs, which is the only Cruze trim rated above 40 MPG highway. One more thought - try 91 or 93 octane. There is a noticeable improvement for most Cruzen with the higher octane. If you see improvement on premium the question you'll need to ask yourself is "is my cost/mile lower even though I pay more at the pump?"
I am using 89 octane now, but will try higher after I settle the m6 vs leave it in drive thing....

Thanks for all your suggestions - I will let you know how it goes. Any other ideas, just let me know.

Michael
 

·
Premium Member
Joined
·
25,595 Posts
Just to give you some comparison points:

2012 Cruze 1.4T Automatic => 26/38/30 (City/Highway/Combined)
2012 Cruze ECO Manual => 28/42/33 (City/Highway/Combined)

You are nearly 15% above the combined number, which is actually quite good, especially for an automatic transmission. I had a 2013 1LT Automatic for a few days while my ECO was having the HVAC ducting replaced and even with hyper-miling techniques I had a hard time averaging 35 MPG in the car.
 

·
Premium Member
Joined
·
6,915 Posts
The reason you can't seem to get your average above 35mpg on the highway is the amount of city you are driving at low 30mpg. At about 50-60% highway I get 33-34mpg. Combined the car is rated at 30mpg, so this is actually good. However as soon as I get to 70% highway or more with few stops my MPG gets into the 36-40mpg range(2012 1LT automatic).

Yesterday part of my 500+ mile tank was 50 miles on the interstate at 65mph. I reset the trip a mile before I got on when I ramped off I was reading 45MPG on the DIC.

EPA test are done with 91octane(premium) with no ethanol, to get or beat the window sticker numbers it helps to use the same fuel they do.
 

·
Premium Member
Joined
·
5,157 Posts
Ahh, that makes more sense! Thanks for the clarification!

I think the stops and starts are having more effect than what you are giving them. 5 stops in 10 miles averages out to getting up to speed for 2-3 minutes then needing to do it all over again. That's eating a lot of gas. You might try slowing down to 45-50 mph on that stretch if it's safe to do. Then it wastes less gas accelerating the car, and adds maybe 2-3 minutes onto the trip. Just a thought.
 
  • Like
Reactions: spacedout

·
Premium Member
Joined
·
6,915 Posts
Try to find routes with less stop signs, those stop/starts/idling really kill the automatics MPG average. With the short distance and amount of stops your highway route really would not be considered highway as your average speed is still very low overall.

Also it may seem counter productive but instead of going 56mph on the highway go 58mph. This puts you slightly more into the power band of the engine, 2,000RPM vs 1,850rpm and greatly decreases engine load with slight grades on relatively flat highways.

With my 2012 automatic all highway ramp to ramp with the cruise set at 65-70mph is 36-40mpg(pump fill up) in 50degree or warmer weather. all 2 lane highway at 45-55mph with some main street city driving through small towns with very few stop signs is good for 38-45mpg(same weather). What is the possible difference? I always run premium gas.

Most on here see a 2-4MPG increase with premium.
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #10 ·
well, reset trip 2 and I swear my mileage started to increase. (just wierd) Anyway, I did the trip 2 mileage thing for my commute to work (only 1 way so far) this morning and this is what I ended up with:

house to expressway
14.2 miles, 38.5mpg, 43.3mph
Expressway run
23.1 miles, 38.6mpg, 65.9mph.
Expressway to work
3.8 miles, 39mpg, 25.4mph

that is only 1 direction obviously - will be interesting to see what the difference is going the other direction. My only ideas at this point is that the car is starting to learn my driving style (purchased 1 month ago with 9,000 miles on it and have regapped plugs, but did not disconnect the battery to force the learning cycle) OR I am just driving it a lot more for non-commute driving that I thought and that is driving down my average mileage.

When I took the long trip 2 weeks ago (over 400 miles mostly expressway) I just could not get over 34-35mpg average (the average only increased when I got off the expressway and drove 2 lane roads heading from there to my house) Anyway - I will continue to monitor it and let you all know how it ends up.

Thanks again for all your suggestions.

Michael
 

·
Premium Member
Joined
·
1,351 Posts
Love my Eco 6MT. I don't know why you didn't buy an Eco if you're a hyper miler? I hit the highway for my 56 mile commute, set the cruise at 72 (65 speed limit) and get off the highway, check the DIC and I'm at mid 40 to high 40s. Without the "drive in the slow lane under the speed limit shenanigans." Nothing sucks worse trying to get off the highway from 70mph trying to dodge someone driving 55 or under, in the slow lane to save a dime on gas. But hey... To each his own.

Tire pressure 35 psi @ all 4

Speedometer Auto part Odometer Display device Font



Sent from AutoGuide.com App
 

·
Premium Member
Joined
·
2,704 Posts
Love my Eco 6MT. I don't know why you didn't buy an Eco if you're a hyper miler?
He didn't buy an Eco because he didn't want to buy an Eco. Not everything is about fuel economy. Put it in perspective, the Eco gets ~10% better fuel economy. However, it is also a cheaper car than a 2LT or LTZ. It doesn't have a sport suspension, disc brakes, RS package, etc. It is what it is.

To the OP, try not to run your heat in the morning when its cold so that your car warms up faster. Also, wind direction and speed is the biggest factor in fuel economy when cruising. Nothing you can do about that really.. some days you may get over 40 MPG, some days you may get 35 MPG.
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #13 · (Edited)
Love my Eco 6MT. I don't know why you didn't buy an Eco if you're a hyper miler?
I'm not really that much of a hypermiler - actually got a ticket for 55 in a 50mph work zone last year and $800 later, decided speeding was just not worth the added expense. (at least for 5mph.) Due to that I started driving about 1mph over the speed limit (to keep from getting run over) and have just always drove with the cruse control in all my cars (which happens to work REALLY well on the cruze auto...)

My main thing against the Eco was my wife had to be able to drive it and that required an automatic, not a manual. that dropped the MPG difference down to about 1. (according to the window sticker anyway) The other thing was I really wanted leather seats and they are just not available on the Eco for some unexplainable reason. (plus purchasing used, my options were a little more limited than if I was purchasing new. Not a lot of used Eco models in the area)

Anyway - that was my reasoning. Nothing against the Eco at all, but if limited to an automatic the MPG difference was not enough to make it a "must have" and there were oddly limited options for that trim that made the LT2 a better choice for me. (I like the disk breaks and suspension upgrades as well)
 

·
Registered
Joined
·
60 Posts
Discussion Starter · #14 ·
Well, much better mileage on the way home. Not sure if its the roads, wind or warmer temps (50's on the way to work, high 80's on the way home)


Work to expressway
3.4 miles, 28.9 mpg, 28.2 mph
Expressway to highway
23.3 miles, 43.4 mpg, 64.4 mph (had to slow down due to traffic and a few different turns)
Highway to home
14 miles, 44.1 mpg, 41.6mph.




Not to bad overall. Planning to change the oil this weekend or next. Has anyone seen any MPG increases going from the dealers semi-syn dexos 1 to a full synthetic? (I am going to be using Mobil-1 EP and follow the OCI recommended by the car - whenever it comes up and says "change your oil" I will do it then....)


Michael
 

·
Premium Member
Joined
·
5,157 Posts
Well, much better mileage on the way home. Not sure if its the roads, wind or warmer temps (50's on the way to work, high 80's on the way home)


Work to expressway
3.4 miles, 28.9 mpg, 28.2 mph
Expressway to highway
23.3 miles, 43.4 mpg, 64.4 mph (had to slow down due to traffic and a few different turns)
Highway to home
14 miles, 44.1 mpg, 41.6mph.




Not to bad overall. Planning to change the oil this weekend or next. Has anyone seen any MPG increases going from the dealers semi-syn dexos 1 to a full synthetic? (I am going to be using Mobil-1 EP and follow the OCI recommended by the car - whenever it comes up and says "change your oil" I will do it then....)


Michael
These cars do better at higher temperatures.

Also, go 7500 miles or 25% on the oil life monitor to figure out when to change your oil, whichever comes first. We've found that when the computer says to change the oil is optimistic. And, Mobil 1 EP hasn't shown to do any better than regular Mobil 1 (or any other dexos1 certified full synthetic, for that matter). I change every 7500 miles with whatever dexos1 full synthetic oil is cheapest at the time. They're all very good oils, the only real difference between 5w-30 dexos1-certified synthetic oils is in the name on the bottle.
 
1 - 15 of 15 Posts
Top