Why Is My Gas Mileage So Bad On My Nbs?

[my07silvy]

I have 1500 miles on my NBS 5.3 crew cab silverado....The DIC is only telling me I'm getting 13.5 and I have reset it like 3 times now....I dont drive like a maniac or anything, I drive 50% city and 50% highway...How do u other guys get these crazy numbers? This thing is worse then my 05 tahoe!!! Whats going on someone help!

[Wingnut]

It'll generally get better with a few thousand miles on it...But those wheels are going to be a big factor as well. They're a bear to turn.

[325]

Have you adjusted for the difference in the new tire size and the original factory tire size?

[cerbomark]

an ethonol fuel blend will lower your mileage too. Plus you do only have 1500 miles, everything is still tight.

[2004GMC1500CC]

I have 1500 miles on my NBS 5.3 crew cab silverado....The DIC is only telling me I'm getting 13.5 and I have reset it like 3 times now....I dont drive like a maniac or anything, I drive 50% city and 50% highway...How do u other guys get these crazy numbers? This thing is worse then my 05 tahoe!!! Whats going on someone help!

 

As I was reading your question, I was a bit stumped, until I saw your wheels and tires.

[AllBlkdOut07]

I have 1500 miles on my NBS 5.3 crew cab silverado....The DIC is only telling me I'm getting 13.5 and I have reset it like 3 times now....I dont drive like a maniac or anything, I drive 50% city and 50% highway...How do u other guys get these crazy numbers? This thing is worse then my 05 tahoe!!! Whats going on someone help!

 

As I was reading your question, I was a bit stumped, until I saw your wheels and tires.

 

 

Nothing confusing here. I have 2,300 miles on my 5.3L NNBS SIlverado LT which is currently bone stock. My mileage has been on 14.1 since day one. I drive VERY moderately. Do I have to reset this thing or what? 14.1 MPG stinks considering half of my mileage is highway too.

[VMax2007]

FYI, my MPG is also 14.0-14.1, but I have the 6.0 Vmax with 3.73's and this is ALL city driving with some rush hour (stop and go) inter-city freeway. No true highway mileage yet. I am a fairly easy driver, but I do like to get on her once in awhile, don't we all?

[solarjustin]

Has anyone claculated the milage by hand? I have seen on a number of different cars that have DIC (or some other system) that gives you milage be off as much as 1-3mpg. I guess you could be 3mpg better or worse. Just an idea.

 

I have an 2004 2wd and can 19.3-20mpg on the open road, but city it will drop down to 15-16mpg.

[bigdogxx]

I have 1500 miles on my NBS 5.3 crew cab silverado....The DIC is only telling me I'm getting 13.5 and I have reset it like 3 times now....I dont drive like a maniac or anything, I drive 50% city and 50% highway...How do u other guys get these crazy numbers? This thing is worse then my 05 tahoe!!! Whats going on someone help!

 

 

24" rims is why your mileage has gone to crap.

[my07silvy]

no I just put the wheels on a week or 2 ago....The mileage was the same up until then believe it or not. I have not corrected the speedometer for the tire size change because I will be going back to stocks for the winter...I'm thinking about going for a wait4me tune and see if that helps.

[Wolverine]

Those rims and tires won't do you much good in 4x4 mode I take it... And that could be screwing up your mileage. I have a nbs Z71 4x4 and average 14.8 in city....

[asilverblazer]

My mileage is crappy too. I'd like to ride with these drivers that have extended cab 4x4's with a 5.3L and 3.73 rear end's because I don't have anything on my truck that adds weight, drive very moderately, less than 65mph, no heavy footed accelration, and my best is 16mpg. I don't know how they do it to get 20mpg.

[jwalker]

The 24 inch wheels are causing a havoc with your computer & this giving you false gas mileage info. Plus it's harder for the engine to turn over those "monster truck wheels & tires" lol!

[steppetoe]

Shrug...

 

Everytime I ride with someone who says they get crappy mileage, they are on and off the gas all the time, accelerating, braking, accelerating, braking, etc, much more than they need to be. Plus they always seem to be in the fast lane...

 

Personally, knock on wood, I have always been able to get good mileage with all my cars, I drive light and easy, anticipating the stops, keeping close to the speed limits, only gunning it once in a great while.

 

I am averaging 19.4 right now in my nbs AND that's with the lower front airdam removed and the front end raised 2 inches. That is probably 85/15 highway/city. I have about 4000 miles now. I tend to cruise at between 60 and 65 on the highway. I do have a bed cover.

 

By the way, I have compared the DIC calculations to manual calculations and they are spot-on.

 

P.S. Those 24's can't be helping.

[solarjustin]

It was just a though, the computers I'm sure have gotten better over the years, my 04 does not have the DIC so I only have my hand calc milage to go off. and I too drive almost like a grandma, and keep the tachometer under 2k almost all of the time.