1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

BFG ATs are on and ...

Discussion in '2nd Gen. Tacomas (2005-2015)' started by pcledrew, Nov 11, 2010.

  1. Nov 11, 2010 at 8:03 PM
    #1
    pcledrew

    pcledrew [OP] Well-Known Member

    Joined:
    May 21, 2010
    Member:
    #37558
    Messages:
    344
    Gender:
    Male
    BC
    Vehicle:
    2017 MGM TRD Sport DCLB
    Now I'm getting super shitty mileage. Wondering if there's something I'm doing wrong. Last mileage calc. before swap came out to about 20 mpg (us gal). Since then I've noticed a steep decline after going to the BFGs from the stock sport bridgestones, down to 16 mpg (again, us gal).
    Is this normal? Or something to be concerned about?

    And for all you "it's a truck, not a civic" people, I'm not concerned about the fuel economy, just the drastic change, trying to find out if this is solely because of the tire change, or not.

    Also, would going from a 265/65/17 to a 265/70/16 throw my speedo out badly? It's off by about 7 km/h since the tire swap (and FJ TRD rims).
    Thanks everyone.
     
  2. Nov 11, 2010 at 8:06 PM
    #2
    kinkrider101

    kinkrider101 Well-Known Member

    Joined:
    Sep 29, 2009
    Member:
    #23497
    Messages:
    2,693
    Gender:
    Male
    santa barbara
    Vehicle:
    2007 cummins/2007 tacoma
    wheels and tires
    Well I had 18 before and now like 17
     
  3. Nov 11, 2010 at 8:07 PM
    #3
    PB65stang

    PB65stang Well-Known Member

    Joined:
    Dec 2, 2009
    Member:
    #26900
    Messages:
    1,636
    Gender:
    Male
    First Name:
    Patrick
    Kansas City
    Vehicle:
    2006 Infiniti M35x
    BFGs are super heavy. I put some 265/70/17 Wrangler A/Ts on, and noticed a decrease of about 1 mpg myself, so I'm not super surprised. And yes, your spedometer actually was reading fast before you upgraded size, and is probably right on now. So your mileage was probably overstated earlier.
     
  4. Nov 11, 2010 at 8:08 PM
    #4
    jandrews

    jandrews Carolina Alliance Southwest Region Ambassador

    Joined:
    Jun 7, 2009
    Member:
    #18122
    Messages:
    12,180
    Gender:
    Male
    Vehicle:
    '09 FourDubDee TRD OR
    A-TRUCK, Fat Kid in the Bed, Custom Pinstriping, Ported and Polished Muffler Bearing, Hi-Performance Bed Mat
    It's a truck, not a civic.






























































    But seriously, the BFGs have a more aggressive tread pattern, and that's going to create additional resistance. Also, the BFGs are likely a heavier tire than your stock tires (stock tires are almost always shit).

    What size tire did you have? What size tire now? What weight of wheel then? Now?

    Tire pressure up to spec?

    Is this mpg based on one tank, or several? Because to determine TRUE MPG trends, you need to look at an average over several tanks of gas.
     
  5. Nov 11, 2010 at 9:01 PM
    #5
    tuckr2

    tuckr2 Well-Known Member

    Joined:
    Nov 17, 2009
    Member:
    #26115
    Messages:
    739
    Gender:
    Male
    Western Washington State
    Vehicle:
    2010 Silver dbl cab LB 4x4 It's Purdy too!
    LT265/70/17 BFG A/T's, Disabled Seat Belt Buzzer, Black and Gray Covercraft Seat Covers front and rear, Matching SnugTop Supersport Canopy, undercoat, bed mat, window vent shades. Black Weathertech Liners. Trans TSB, Rear Spring TSB Installed.
    Yeah, I feel your pain.
    While I bought the truck for it's good looks and gas mileage (prior F150 supercrew), I hated the stock sissy tires.
    Put on BFG AT's, 265/70/17, load range C. Heavier tire and immediately the gas mileage dropped from about 17 in town to 15. Taller tire than stock changed to speedo reading, it's actually spot on now.
    I don't hit the highway much but last short road trip saw about 18.5 mpg. Better than my Ford, but nothing to get all excited about. In the end I bought the tires for the added off-road capabilities so I got what I expected.
     
  6. Nov 11, 2010 at 9:09 PM
    #6
    pcledrew

    pcledrew [OP] Well-Known Member

    Joined:
    May 21, 2010
    Member:
    #37558
    Messages:
    344
    Gender:
    Male
    BC
    Vehicle:
    2017 MGM TRD Sport DCLB
    Jandrews: good call. As for the mpg reading, it's been the same fuel usage for about 250 k of driving 3 trips in a row now. All this is highway too by the way.

    As for tire size theories, my tire is actually near the exact same diameter, and according to the tire calc, should only effect my speedo by less than 1 mph. Remember, it is a "70" but on a 16 rim, not 17.

    It is possible my speedo has been out all along. I'll try my next trip with it showing the speed I want to go. Not using gps as a speedo.

    Thanks for the responses so far. Keep the ideas coming.
     
  7. Nov 11, 2010 at 9:18 PM
    #7
    jdtemple

    jdtemple Well-Known Member

    Joined:
    Apr 19, 2010
    Member:
    #35623
    Messages:
    517
    Gender:
    Male
    Bay Area CA
    Vehicle:
    08 DBLCAB LB TRD Sport
    Lift & Tires, in cab power outlets, Locking Bed Boxes, K&N
    Whats your cruising speed? I can squeeze 19-20mpg on mostly highway driving. Are you a fast accelerator? Happen to be driving into the wind? Lots of things will change MPG. What PSI are you running?

    Heavy Tires = More Rotating Mass = More right foot to get to cruising speed.

    PS Check out my fuelly log, and add 6.6%. so 16.3mpg x 1.066 = 17.35. My best tank at 21.1 is actually 22.5. (Tire diameter difference vs odometer)
     
  8. Nov 11, 2010 at 9:39 PM
    #8
    island808

    island808 Me l've got brains.

    Joined:
    Oct 9, 2010
    Member:
    #44414
    Messages:
    1,892
    Gender:
    Male
    First Name:
    Jedediah
    hawaii
    Vehicle:
    '10 6speed 4x4 access cab
  9. Nov 11, 2010 at 10:32 PM
    #9
    OZ-T

    OZ-T Quite an experience to live in fear , isn't it ?

    Joined:
    Dec 15, 2009
    Member:
    #27584
    Messages:
    38,701
    Gender:
    Male
    First Name:
    Peter North
    British Columbia
    Vehicle:
    Mag Grey 09 Trd Sport DCLB 4x4
    OME 885x , OME shocks and Dakars , Wheelers SuperBumps front and rear , 275/70/17 Hankook ATm , OEM bed mat , Weathertech digifit floor liners , Weathertech in-channel vents , headache rack , Leer 100RCC commercial canopy , TRD bedside decals removed , Devil Horns by Andres , HomerTaco Satoshi
    OP , my mileage dropped a bit when I went to heavier E rated tires , and went up to 265/70/17 ( I realize you are 265/70/16 ) .

    I'm suprised that you have had such a big decrease going to a C rated tire which is virtually the same size as stock . Any chance your tire change coincides with the Alberta winter kicking in ? Colder weather , use of 4x4 will decrease your efficiency .
     
  10. Nov 12, 2010 at 12:43 AM
    #10
    TACOMA TRD

    TACOMA TRD Well-Known Member

    Joined:
    Apr 9, 2010
    Member:
    #34897
    Messages:
    2,207
    Gender:
    Male
    First Name:
    Tom
    PA
    Vehicle:
    2011 MGM SPORT DC 4x4
    Alpine HU, Apline 6.5 3 way Speakers, Access Cover.
    I put BF's on my Dakota, mileage went to hell. They are a very heavy tire and designed for off road use. Not fuel economy. I went with the Grabber AT2 this time, mileage did'nt suffer too much. Lost about 1 mpg from stockers. I think from moving from a 17 to a 16, is throwing off your speedo and mileage. Use a gps and figure out your speed vs odo.
     
  11. Nov 12, 2010 at 4:29 AM
    #11
    jandrews

    jandrews Carolina Alliance Southwest Region Ambassador

    Joined:
    Jun 7, 2009
    Member:
    #18122
    Messages:
    12,180
    Gender:
    Male
    Vehicle:
    '09 FourDubDee TRD OR
    A-TRUCK, Fat Kid in the Bed, Custom Pinstriping, Ported and Polished Muffler Bearing, Hi-Performance Bed Mat
    You really wanna fuck up your mileage, slap some MTs on there.
     
  12. Nov 12, 2010 at 5:05 AM
    #12
    pcledrew

    pcledrew [OP] Well-Known Member

    Joined:
    May 21, 2010
    Member:
    #37558
    Messages:
    344
    Gender:
    Male
    BC
    Vehicle:
    2017 MGM TRD Sport DCLB
    Noneck: no offense, but please learn to read the whole post.

    Jd: I try to accelerate without jamming on the pedal, and for the most part I'm the slow guy at the lights. As for cruising, about 66-68 mph.

    OZ: winters here yes, but no 4x4 yet. And not really that cold. Maybe it's a speed thing.
     
  13. Nov 12, 2010 at 5:08 AM
    #13
    Taco4x4NC

    Taco4x4NC Well-Known Member

    Joined:
    Feb 2, 2010
    Member:
    #30601
    Messages:
    879
    Gender:
    Male
    First Name:
    David
    Western North Carolina
    Vehicle:
    2010 4x4 DC/LB "Pytrite Mica/Katzkin leather
    3m clear bra or Venture, stant locking gas cap, Shield, front windows tinted, weathertechs, ARE "Z" topper. Sockmonkey decal, Billy 5100's x 4 corners, Eibach coils, Toytec 1.5 AAL. Michelin 265/75/16 MS2's, Grillcraft MX series/TOYOTA badging. FJ/SE TRD Anthracite gray wheels. Katzkin leather/heated seats.
    BFG's as stated.....a heavy tire, gas mileage will drop with a heavier tire.
     
  14. Nov 12, 2010 at 11:19 AM
    #14
    PB65stang

    PB65stang Well-Known Member

    Joined:
    Dec 2, 2009
    Member:
    #26900
    Messages:
    1,636
    Gender:
    Male
    First Name:
    Patrick
    Kansas City
    Vehicle:
    2006 Infiniti M35x
    Just so we are clear for everyone who thinks they're mileage dropped when getting bigger tires - it was overstated with your old tires. If your spedometer was reading fast, your truck was accumulating more miles than you were really driving, so your mileage incorrect, about 5% on mine I believe. So even though I thought I was getting 20 mpg, I was really getting 19. So with my new tires getting 19, I'm actually pretty much the same.

    You can't have the best of both worlds...higher mileage with shorter tires, and more accurate speedo with taller tires. Just making sure everyone is on the same page...I think some guys ignore the fact that the 20 mpg they thought they were getting was never happening. :thumbsup:
     
  15. Nov 12, 2010 at 11:27 AM
    #15
    PB65stang

    PB65stang Well-Known Member

    Joined:
    Dec 2, 2009
    Member:
    #26900
    Messages:
    1,636
    Gender:
    Male
    First Name:
    Patrick
    Kansas City
    Vehicle:
    2006 Infiniti M35x
    If you use a GPS, then you're fine. I'd say most people (myself included) don't, so you have to make the adjustment.

    EDIT: Yeah, if you get 12-13 mpg, then you have some issues.
     
  16. Nov 12, 2010 at 2:39 PM
    #16
    jandrews

    jandrews Carolina Alliance Southwest Region Ambassador

    Joined:
    Jun 7, 2009
    Member:
    #18122
    Messages:
    12,180
    Gender:
    Male
    Vehicle:
    '09 FourDubDee TRD OR
    A-TRUCK, Fat Kid in the Bed, Custom Pinstriping, Ported and Polished Muffler Bearing, Hi-Performance Bed Mat
    Easiest solution is to not give a shit. When gas needle gets near E, put in more gas. Simple.

    Not at all. Once you lift these things, put 33 - 35" tires on them, along with a full set of armor (an extra 400 pounds or more), 12-13 mpg around town is easily attainable and absolutely nothing is wrong with the vehicle.

    See above: When gas needle gets near E...
     
  17. Nov 12, 2010 at 7:00 PM
    #17
    JATaco

    JATaco Well-Known Member

    Joined:
    Aug 15, 2008
    Member:
    #8551
    Messages:
    125
    Las Vegas
    Vehicle:
    tacoma prerunner
    I just bought some 17 in xd rims. They had some maxis bighorn m/t, im getting 15 mpg, but my truck looks badass.

    '
     
  18. Nov 12, 2010 at 11:38 PM
    #18
    OZ-T

    OZ-T Quite an experience to live in fear , isn't it ?

    Joined:
    Dec 15, 2009
    Member:
    #27584
    Messages:
    38,701
    Gender:
    Male
    First Name:
    Peter North
    British Columbia
    Vehicle:
    Mag Grey 09 Trd Sport DCLB 4x4
    OME 885x , OME shocks and Dakars , Wheelers SuperBumps front and rear , 275/70/17 Hankook ATm , OEM bed mat , Weathertech digifit floor liners , Weathertech in-channel vents , headache rack , Leer 100RCC commercial canopy , TRD bedside decals removed , Devil Horns by Andres , HomerTaco Satoshi
    FWIW , I have 265/70/17 E rated Hankook Dynapro MT's and get 19 MPG with rural driving .
     
To Top