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sele's avatar
sele
Explorer
Jul 30, 2013

mpg f150 ecoboost to lock out 6th or not

So here is my question when i select tow haul should I lock out 6th or not. Here in good old flat illinois I have no issue pulling in 6th gear rarely downshifts to 5th. The eingine is running at about 1800 rpm and i am getting between 9 and 9.5 mpg. I have locked out 6th when we have been in the Ozarks and then the engine is running about 2200 rpm as a norm but haven't checked milage. I wonder if by locking out 6th gear and keeping the rpm up which is closer to the pwoer band if I would see better mpg? Also even though the rpm is lower is the engine lugging more? More of a curiosty issue than anything. Over all I am very happy with the prefomance. WE have about 1800 miles towing so far with no issue. But I would not go any larger that what we currently have.
Tow Vehicles

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  • bimbert84's avatar
    bimbert84
    Explorer
    Aug 03, 2013
    I recently completed my first tow trip with my Ecoboost. On the way out, I left it in 6th (1600 RPM), which it held most of the way, and got 8.5 MPG. On the way back, I capped it at 5th (2100 RPM) and got 9.2 MPG.
  • Buck50HD's avatar
    Buck50HD
    Explorer
    Aug 02, 2013
    6th gear = 6-8psi boost at 1750RPM
    5th gear = 1-3psi boost at 2150RPM

    Both offer nearly identical mileage and quiet towing. I like 5th with less cylinder pressure and no downshifting on grades <5%.

    My only exception is with a good tailwind, I'll kick it into 6th.
  • Shadow_Grey's avatar
    Shadow_Grey
    Explorer
    Aug 01, 2013
    Howie3 wrote:
    Great question. I have the same truck with 3.73 axle. My experience (though not scientific)is that I get better mileage at the lower RPMs in 6th gear, so if the truck will maintain 6th on its own, I let it do its thing. The exceptions would be a headwind, a slight uphill grade, or if I am travelling under 55 mph. In these cases the truck may tend to lug a bit, even though the low end torque maintains 6th gear. I then lock out 6th as it 'feels' better and the truck is more responsive and it's probably a little easier on the transmission. I don't think the difference in fuel economy would be significant in either case so I go with the most comfortable towing experience in each given situation. The Ecoboost is so quiet regardless of the gear.


    +1 on this...
    If you don't tow with one you don't know...

  • FishOnOne's avatar
    FishOnOne
    Nomad
    Aug 01, 2013
    Turtle n Peeps wrote:
    sele wrote:
    yes i do use the tow haul mode which does gear ratio but in doing so i have the option of locking out the 6th gear which is the highest od Also For information i do have 3.73 rear end my thought is that locking out sixth the engine would be in fifth and closer to the power band thus possibly improving preformance and mpg.


    If you are looking for mileage it's simple, just look at the boost gauge. The closer you are to vacuum the better. If you are in vacuum, the higher the vacuum the better. Anytime you're in boost your making your engine bigger and it will gulp more fuel. At full boost that little 3.5 thinks it's a 7.0 liter engine. You want it to think it's a 3.5 liter as much as you can.

    Try it in both gears and see which is better.


    Turtle,
    Can you be a little more specific which boost gauge you're referring to? :W

    Is your recommendation based on your own experience or your friends again? :W
  • Perrysburg_Dodg's avatar
    Perrysburg_Dodg
    Explorer
    Aug 01, 2013
    In the new transmissions the tow/haul does change the shift pattern by increasing the line pressure and also holding the shifts longer. I do not believe the new trans has a true OD anymore does it?

    My 04 the T/H button locks out the OD that's it. Yours it does a whole lot more. Might want to talk to a trans shop that works on Ford's to get the real skinny.

    Don
  • Howie3's avatar
    Howie3
    Explorer
    Aug 01, 2013
    Great question. I have the same truck with 3.73 axle. My experience (though not scientific)is that I get better mileage at the lower RPMs in 6th gear, so if the truck will maintain 6th on its own, I let it do its thing. The exceptions would be a headwind, a slight uphill grade, or if I am travelling under 55 mph. In these cases the truck may tend to lug a bit, even though the low end torque maintains 6th gear. I then lock out 6th as it 'feels' better and the truck is more responsive and it's probably a little easier on the transmission. I don't think the difference in fuel economy would be significant in either case so I go with the most comfortable towing experience in each given situation. The Ecoboost is so quiet regardless of the gear.
  • APT's avatar
    APT
    Explorer
    Jul 31, 2013
    I suspect 5th gear will be slightly better with improved throttle response.
  • Turtle_n_Peeps's avatar
    Turtle_n_Peeps
    Explorer
    Jul 30, 2013
    sele wrote:
    yes i do use the tow haul mode which does gear ratio but in doing so i have the option of locking out the 6th gear which is the highest od Also For information i do have 3.73 rear end my thought is that locking out sixth the engine would be in fifth and closer to the power band thus possibly improving preformance and mpg.


    If you are looking for mileage it's simple, just look at the boost gauge. The closer you are to vacuum the better. If you are in vacuum, the higher the vacuum the better. Anytime you're in boost your making your engine bigger and it will gulp more fuel. At full boost that little 3.5 thinks it's a 7.0 liter engine. You want it to think it's a 3.5 liter as much as you can.

    Try it in both gears and see which is better.
  • sele's avatar
    sele
    Explorer
    Jul 30, 2013
    yes i do use the tow haul mode which does gear ratio but in doing so i have the option of locking out the 6th gear which is the highest od Also For information i do have 3.73 rear end my thought is that locking out sixth the engine would be in fifth and closer to the power band thus possibly improving preformance and mpg.
  • BenK's avatar
    BenK
    Explorer
    Jul 30, 2013
    Automatics are designed for folks who do not want to, or do not know HOW2 manage
    the gears vs situation

    Why automatics now have that 'tow/haul' button...

    Since you have an automatic (it thinks for itself, removes the gear selection
    overhead from the driver, etc), why not use the 'tow/haul' button and leave it
    in the gear your manual says to when using 'tow/haul' and then enjoy the ride?

    Most 'tow/haul' functions will hold a lower gear longer and/or drop to a lower
    gear by itself to reduce the strain on the drive train when 'towing' or 'hauling'...

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