Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!





Chevy Silverado and GMC Sierra Real World MPG Numbers

1234568

Comments

  • ttaupier1ttaupier1 Posts: 50
    Hi INHAL,

    I have a 2003 GMC sierra 5.3. 130k miles... I bought new and have been testing the waters on many things, first thing i did was a tonneau covers hard plastic wrap over, +2.5mpg, then i did the K&N pfikit +1mpg, then i upgraded my wheels and tires to a more highway +1mpg, i tried the mass flow sensor from gannelli? both the K&N version and the plain version.. neither worked 1200 lost... then i replaced all gear lube in trnasfer cases mobil1 synth (+1mpg), i also did the auto transmition fluid in synthetic $55/qt mobil1 +1 mpg. I also ripped the mechanical fan off the front and installed a flexlite kit (runs cooler more HP ... no milage..) also in the winter the truck heats up better...

    MPG average to date 18.0 town...20.5 highway ( not drafting)

    next steps are exhaust and diablo code change/re-maper DiabloSport Trinity Tuner, Monitor: Gas and Diesel (T1000) so far this is the only one i have seen real results from ...
  • 2doorpost2doorpost Posts: 74
    I had the same thing going on with my 08 Silverado. Fuel miliage fell to below 15 MPG HWY.(and I have the 4.3 V6 without A/C) Truck had 55000 miles.

    I had the fuel injector system cleaned out by the dealer. The truck runs better and the gas miliage is the best its ever been. Just a tad over 20 MPG HWY now.

    I always changed the oil regularly, and the air filter, but skipped the fuel system maintenance.

    Never again.
  • Stever@EdmundsStever@Edmunds YooperlandPosts: 38,919
    A reporter wants to talk with people who expected to get better gas mileage in their relatively new vehicle. Please email pr@edmunds.com by Tuesday, July 19, 2011 with your daytime contact information and a few words about your experience. Thank you.
  • 2001 silverado ext cab 4x2 4.8L 1200 miles purchased new 30 days ago.



    Round trip, Ocala florida to Orlando area. tripometer- 235 miles used a full tank + (26 gal +)

    I had the truck to the dealer twice so far in reguards to mileage and the way it runs ** crusing, accelerate slightly, slight enough that it does not down shift and is bucks, like a miss under load, also noticed this condition when in a parking lot, slow holding steady low speed, it feels like your applying light pressure to brakes and letting off (repeating). And other possible related condition, slowing to a stop, close to stopping the truck surges like accelerator is tapped. Sometimes applying slight brake others just letting off to coast toward light. This has happened 4 to 5 times since bought. **AND YES I AM SURE I WASN'T TOUCHING THE GAS PEDAL**



    No check engine light, dealer states it was scanned with no codes present. I noticed these things in the first week of ownership. The service advisor told me there was probbably some water in the fuel, and that I need to find a new place to fuel up ***this was the complementary tank of fuel at purchase*** and I have fueled at 5 different places since and no changes.


    I feel as if I have purchased a sick, hungry St. Bernard
  • My "96 4x4 Yukon w/5.7 Vortec gets upwards of 19.5 "corrected MPG at 55mph or Less using Hypermiling techniques and 45psi

    At 75-85mph I can get 17.8mpg, with AC on
    This on a vehicle with 225,000 miles AND 4x4 !
    My axle is very low, speeds over 55mph cause the tach to rise rapidly.

    A major factor is the fact I can get fuel with NO MTBE or Alcohol !

    MTBE is mandated for townships upwind of major cities, it supposedly is an oxgenator type additive.

    Alcohol had about 80k BTU/Gl
    Gasoline has about 115k BTU/Gl
    Less BTU = less energy

    Use Hypermiling techniques when you are not in traffic situations.
    Keep the air pressure at absolute MAX without causing wear issues.
    Keep the oil changed.
    Forget K&N Air Filters or big exhaust for fuel economy.
    Use the hottest thermostat and plugs you can find.

    Best Luck
    DrVette
  • redwing, I had a 2500HD with the 8.1 liter engine. i got 11.00 m.p.g. in town and 12.6 on hwy. it is a real work truck. great for towing and hauling heavy loads. i dont think the mialege would change much pulling a trailer. i pulled a car trailer and couldnt tell it was there.
  • I have a 2010 gmc 1500 5.3 reg cab 4x4 with a procomp 6" lift , 32.2" good year dura track tires, magnaflow cat back 2-1-2 exhaust exhaust and a edge evolution chip (only running on trans tune to firm up the shifts) i get a consistent 17.5 mpg and thats going 45-55 mph in 4x4 on some extreamly icey roads between jasper and banff about 200 kms or 135 miles and when it cleared 80 mph on a fairly straight road with little traffic still some 6% grades in there for another 350kms or 210 miles and i get about 17.5 mpg so some 550 kms on 86 litres of fuel with my heavy foot in a more than capable 4x4 17.5 mpg is is pretty damn good

    2009 f350 6.4 diesel drw cc gets 8mpg and my 2011 f350 6.2 gas drw cc gets about 8 mpg( im so done with diesels !!!!!! aswell and my wifes 2008 honda civic gets 48 mpg on the hwy all day long!!!!!!

    long story short if you want fuel economy buy a civic or similar vehicle if you wanna drive a truck be prepaired to pay more in fuel if you want cc drw 4x4 hope its making you money because thay are thirsty!!!!!!

    i also have a 1991 s10 with a supercharged small block that gets 6 mpg on premium but runs the quarter in 12.5 at 110 mph but cant complain at paying a little extra for a good time :D :D
  • I now have about 5000 mi. on my Silverado. Just filled up AGAIN with 21.2 gallons of gasoline. My gauge showed 321 miles since last fill up. My Active fuel management won't work above 60-65 MPH, therefor I don't get the benefit from the Active Fuel Management at normal highway driving around 70 mph. GM has looked at it and assures me that it's operating normal dispite their misleading epa window sticker 15 city 21 highway.

    I get about 15 city 16 on level highway above 65 MPH. Not loaded and I don't have a heavy foot. gas - Shell, Exxon, Chevron

    321 miles divided by 21.2 gallons gas = 15.14 MPG city miles 50% highway 50%

    Since the Active fuel Management is not designed to work above 65 MPH on level highway, I can't get the fuel savings at the highway speed of 70 -72 MPH. I don't know why they designed it that way, but GM says that's normal. Are they lying to me ?
  • I now have about 5,000 mi. on my Silverado. Just filled up AGAIN with 21.2 gallons of gasoline. My gauge showed 321 miles since last fill up. My Active fuel management won't work above 60-65 MPH, therefore, I don't get the benefit from the Active Fuel Management at normal highway driving around 70 mph. GM has looked at it and assures me that it's operating normal dispite their misleading epa window sticker 15 city 21 highway.
    I get about 15 city 16 on level highway above 65 MPH. Not loaded and I don't have a heavy foot. gas - Shell, Exxon, Chevron

    321 miles divided by 21.2 gallons gas = 15.14 MPG city miles 50% highway 50%

    Since the Active fuel Management is not designed to work above 65 MPH on level highway, I can't get the fuel savings at the highway speed of 70 -72 MPH. I don't know why they designed it that way, but GM says that's normal. Are they lying to me ?
  • chuck1chuck1 Posts: 1,405
    edited January 2012
    Mine works at 70mph. However, after 70mph it will not come on much. I have 10,000 miles on my truck. Three trips to Utah and one to Sedona, Arizona from Southern California.

    OVERALL mpg is showing 15mpg. I get 12 to 14 city...depending. This takes in the very short around town trips and the 20mpg I get on the highway.

    Speeds above 70mph will net 17.5 to 18.5 w/o active fuel management coming on.
  • string2string2 Posts: 71
    OVERALL mpg is showing 15mpg. I get 12 to 14 city...depending. This takes in the very short around town trips and the 20mpg I get on the highway.

    Speeds above 70mph will net 17.5 to 18.5 w/o active fuel management coming on.

    Hi Chuck1
    I sure would like to get 18.5 miles on the highway without AFM. Especially if (at some future time) it would, miraculouslyly, begin to start activating the AFM at higher speeds.
    My AFM, at low mileage, works okay up to about 52 MPH then drops off quickly. Past 52 it just activates for very short distances on level highway, then activates less often up to about 63 MPH. After that, it only works going down hill. I only get 16 MPG w/o AFM driving about 70-73. I get about 15 in town. GM tells me it is operating normally?
    String
  • Hey String, I just bought my brothers 2011 Silverado 1500 CC 4x4 5.3L flex fuel. Truck has 7,500 miles on it and same thing, active fuel management doesn't switch on unless your going down hill or slowing down. Instant Econ. gage said 12.5 on a 20 mile trip on flat straight highways at 60mph Burning E-85. Even with 89 Octane it only got 14 at 65-70 highway speed. I bought a superchips programmer and am anxious to see if a fuel map has more than a 2MPG difference. It is rocking 33s with the factory 20" rims. Wondering if you ever pinpointed the issue???
  • Hi Cabe227,
    Doesn't that really hack you off! No, I haven't found the problem yet. And since there is no trouble code, I'm stuck. I've been considering getting an aftermarket program fix, but I keep hoping it might correct itself, but I'm pretty sure that's not going to happen.
    I prepared a letter earlier this month, outlining all the poor gas mileage & Active Fuel Management problems i'm having with my truck and sent it CERTIFIED Mail to BILL SUESSMAN, who is the General Manager of Ron Craft Chevrolet in Baytown, Texas. I've gotten no response. He has ignored my letter.
    Please let me know if your programmer worked for you! My overall mileage right now shows 14.7 MPG. I drive about 60% at 60 - 70 MPH. MY Active Fuel Management system rarely works at that speed, except when going down hill.

    Someone else may have previously found out what the fix is to this problem and will respond on this post, I hope
  • I reset my average MPG meter and drove about 100 miles 15 in town the rest on a 55 MPH highway. running E85 I'm only getting 10.7MPG. I'm planning a trip to the east coast (~1000 miles) and plan on switching to 87 or 89 octane. I hope the superchips Cortex computer can help me get atleast 15 MPG. Im thinking that our trucks are just a bad batch and there isnt enough of them out there for a recall. With the 3.42 gearing and 6-speed transmission and the 5.3 motor we should be getting 18 or better. My 2005 GMC had 4.10 gears and a 5 speed OD tranny with the 5.3 and it got 18+ hwy with 33" tires. Anyway, the computer will be here this week so ill be sure to post results, E 85 and 87-91
  • chuck1chuck1 Posts: 1,405
    E85 will net you lower mpg. I get 12 to 14 on 87 around town. So the 10ish on E85 doesn't sound outlandish.
  • If it helps. I have an 02 Z71 with the 5.3 and 3.73s. It has 79000 miles on it. I drive it 25 miles to work w/8 trafic lights and 3 stop signs. I upgraded the truck with a K&N system and a Flow Master cat back. I get 17-18 mpg around town and 18-19 mpg on highway (w/east coast hills). I have found it gives me a lot more bottom end power also. Big key I have found over the years is More air in and out helps alot. Gota let the truck breath.
  • Hi icmoore2,
    Does the K&N System have anything to do with changing the computer programming that might void the warranty? Is this system one that you order and put on yourself or is it something you need to have installed?
    What kind of gas mileage were you getting before you upgraded to the K&N system?
  • solerisoleri Posts: 4
    Come on guys, all you silverado owners need to quit lying to yourselfs. I accepted & came to terms with the mpg my Truck gets. Here's the figures driving it like theres an ege between the gas pedal & the floor. 11 city 16 hwy at 70 mph. This is horrific! I thought something was wrong till I talked to a Co. worker that had same truck. SAME MPG numbers. And dont go by that dumb computer on the dash. Chevy just put that there to make us feel better. Calculate at the pump. "miles driven divided by gallons of gas used". Only way to get tru figures. Im going back to my 86 toyota 4 banger. Never let me down and get 23 on the hwy all day long, and is a lot funner & easier to work on. And can actually hold its own off road. Accept what you get, you'll feel better after. Id sell while you still can before gas goes up anymore. Mines worth less than half of what I paid for it after only 55,000 miles. Just my 2 cents worth guys.
  • chuck1chuck1 Posts: 1,405
    "16 hwy at 70 mph"

    This is much less than others. Couple of questions-

    Did you add bigger tires?
    Do you have a lift?
    Do you have a CAI?
  • ttaupier1ttaupier1 Posts: 50
    Hi String, I have a GMC sierra 2003, SLT, 17 in Denali take offs wheels, 32.5 Yokohama ( M&S), "NO LIFT" ...I run mobile 1 synth in tranny, and diffs (expensive tranny fluid). I have a KN FIPK, and stock exhaust, I have a 300# bed cover-fiber glass and painted. Tire pressure I maintain about 35# every tire. My best all around mileage is about 17.9, ....if I spend 80% on highway .. usually around 18.7mpg for longer trips ( 60-75mph). If I keep it near 65 mileage goes to 20-21.... this is in the northeast and tons of hills. Long drives on back roads ..no lights or stop signs upper NY ...im 21MPG,

    I also installed an electric fan ( and took the crank shaft weight off motor) FLEXLITE - engine seems much happier starts easier runs smother.. and punch is great at rear wheels.. i have heard 10 % low end HP but have yet to measure rear wheel HP

    exclusively city I'm about 14.5 like jersey city
Sign In or Register to comment.