56rat

I need to see better mileage out of my 2012 EB FX4 4x4 because I daily drive it. I have a cover on the bed and I baby it everywhere I go. I was only seeing ~15.4 mpg average when the truck was 100% stock and I have since added an AFE intake and a SCT hand held and my mileage has tanked. I am averaging 12.9 - 13.5 now. I have tried the 91 and 87 tune with no improvement. Sure, it makes more power ( I have a dyno graph ) but the mileage is way worse.. When I installed an edge chip on my duramax my mileage went way up, I thought I would see similar results with my EB. I was averaging around 18 mpg with my duramax and sold it to buy my EB and I can't believe how much worse of mileage my 6 cylinder truck is getting over a full size 4 door 1 ton diesel.

I spent 350.00 on programmer and another 300 for intake. Was this a total waste of cash? Has anyone had good luck? If so, what in the world am I doing wrong? I thought my 600+ investment would at least jump me up to 17 average MPG or at least close to what my diesel was getting, I surely didn't expect to go the other way. I am at the point of putting my truck up for sale. I LOVE the truck, it's so nice but I can't afford to daily drive it if I am getting this kind of mileage. I thought having a 6 cylinder would really help. I am open for any suggestions on how I can bring my mileage up to ~18 mpg average because there is no reason it should not be able to do it!! Thank you.

FosterChild

Are you using the canned tunes that came with the tuner? If so might want to try to get a custom tune written by a reputable person and go from there. My 5.0 was running about 17.6 . Added tonneau cover and jumped to 18.0 with same style driving. Will be getting livewire and other upgrades in the future

56rat

That's crazy you were seeing 17.6 to begin with. Mine has a tonneau as well. I thought the EB engine brought higher MPGs than the 5.0 and 6.2. I'm sure if I would have known ahead of time that a 5.0 will get me almost 18mpg I would have purchased one of those over my EB. I heard about all these people getting over 20mpg with their ecoboost and that's what convinced me to sell the duramax and buy one. I Have BABIED my truck and have never seen 16mpg yet. I may be having buyers remorse here soon. I spent a boat load on the truck and I guess I should have researched it a little more before pulling the trigger.

I am using the stock, pre loaded tunes that came with the hand held. I never had any dyno tuning done on my diesel and the MPG gains were incredible with just the factory incuded tunes. Isn't that the point of buying a hand held in the first place? I understand there are people who wants a full on dyno tune but when SCT claims mileage gains out of the box I expect to see them without investing hundreds more for another tune.

I am not sure where to turn for custom tunes. The shop I purchased the tuner from owns a dyno and they are a tuning shop but they told me it's not worth paying for a custom dyno tune because SCT has thousands of hours on their tunes on thousands of different trucks and the gains from a custom tune are not worth the money. I just can't believe with all the technology we have now days I cannot get my truck to even get 16mpg, It's a big let down for sure. I love every single thing about my truck except the mileage. I don't want to invest another 600 bucks if I wont get the gains i'm hoping for. When I am driving 500 miles a week it adds up fast.

I thought my duramax was diming me to death. If only I knew then, what I know now I wouldn't have sold it. I'm trying to figure out the best way to bring the mileage up without throwing money in the wind. That's why I am on this forum so I can talk to fellow 150 owners, who have been where I am right now. Thank you for the reply. I'm up for any suggestions that you may have.

Also, how come manufacturers can full out lie about their mpg claims? they rate my truck at 16-22 and I have NEVER seen 16 before.. not even full on highway trips at 70mph.

papa tiger

Make sure your tires are up there in inflation. What axle ratio do you have ? The tonneau may actually not work so well at the tail gate and cost you some mileage, remove it and go back to OEM tunes. You will get your best mileage at 55/62 mph after 10 miles to warm up. Running MT and at those speeds after 200 miles you should see near 20 if you are around 200 lbs or under.

56rat

I am right at 200lbs. My truck has brand new tires and they are all at the correct PSI. I can remove the toneau, It's more of a pain than anything to be honest but it's sure nice for storing things without the worry of having them stolen. Truck has 3.73 ratio. 97% of my driving is city.. stop and go traffic. is there anything that can be done to increase city mileage? If not, I will have a for sale sign in the truck by weeks end which really sucks because it is a great truck. I just can't afford to drive the damn thing. a 2012 6 cylinder 1/2 ton truck should get better than 14 mpg.

NASSTY

97% city? Ouch...the EPA rates the truck for 15 MPGs city. Are your new tires larger than stock?

FosterChild

There mpg rating are based on speed limits. If I stay around 65 I get right at 17.9. Anything above 70 and it drops. I am also not one of those drivers to nail the throttle from a stop and then hit the brake at the last second at stops. I'm not a grandpa just coast into a stop. It helps quite a bit actually.

The city driving is killing you for the most part. Maybe try another route even if it's a little longer with fewer stops it would help some. Good luck and I hope you get it figured out. These are all nice trucks.

Jus Jim

Welcome to the forum.
How are you calculating your mpg? There is a setting in the tuner for tire revolutions per mile. If that happens to be set wrong it will hose up your speedometer / odometer. Double check and make sure it's set correctly for your tire size.
I don't have an EB but I do run a tune. I didn't see any change in my mpg at all. I wanted better shift points and that worked out well for me. There are at least 3 vendors in the forum that write tunes. More Power Tuning, 5 Star Tunes and Livernois are the ones that come to mind. The cost of a tune is about the cost of a tank of gas so it may be worth it. Also, you already have some data to share with a tuner that may be helpful.

SkiSmuggs

I would go back to the stock intake first, because any loss of low end hurts city driving. But Jus Jim may be onto something also. My mileage improved with the SCT canned 87 and 91. My mileage during the winter for a 50 mph commute of 70 miles dropped to 17 over the winter. I had switched to the cheapest gas, Gulf 87. Toward the end of the winter, I got a good deal on Exxon, switched to their 93 and my mileage went to 18-19 from that change alone. Most of the time I run 93 fuel with an 87 or 91 SSi street or tow tune and get 20-21 over my commute.

BucketMan

I do about 97% city too, only highway for road trips, truck is almost 3 years old and has just over 16k on it.

I get about 16 city and my truck is heavier than yours. Try running 89, 91 or 93 in it.

While the tuner has a good bang for the buck ratio, the CAI was unfortunately a bad purchase.