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Auto Braking Sytem

Discussion in '2nd Gen. Tacomas (2005-2015)' started by Maple85, Mar 25, 2009.

  1. Mar 25, 2009 at 1:28 AM
    #1
    Maple85

    Maple85 [OP] Well-Known Member

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    Lots to come at some point. Hopefully soon.
    So I just bought a used 2006 AC Auto Prerunner. It does NOT have the TRD or Off-road package. Anyways I’m still trying to figure a couple things out. First, I have yet to see my RPMS go over about 2000 in any driving conditions. Does that sound normal? Also the Auto braking seems excessive, as soon as I take my foot off the gas the car decelerates rather fast....the strange thing is that it seems inconsistent...sometimes it will do this and other times it won’t. When it has a more "natural" deceleration it tends to almost pick up speed as it slows through about 20-22 MPH range...almost like it kicks into cruise control. So essentially the truck brakes excessively fast OR it will slow to about 20-22 MPH and then stay right at the speed when I should be continuing to decelerate to a stop. I have already kind of asked some of these questions but I’m really trying to pinpoint what these issues could be. Ughhh:frusty:
     
  2. Mar 25, 2009 at 2:23 AM
    #2
    RockDoc

    RockDoc Member

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    You are feeling engine braking. Auto Tranny, I assume? I drive in 4 around town, and the engine braking is less noticable, doesnt shift as much, and feels smoother for stop and go driving. I only go into D on the Highway or freeway. Want to see RPMs over 2000? Drive in 4 over 60 mph, or get on the gas in D and you will see it. Many new owners in this forum, including me, asked the same type of questions. Hope that helps...
     
  3. Mar 25, 2009 at 12:58 PM
    #3
    Maple85

    Maple85 [OP] Well-Known Member

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    Lots to come at some point. Hopefully soon.
    So I put in 4th today and it did seem to handle more smoothly. I also like the fact that the truck doesn't experience that excessive engine braking. So as long as I’m driving in the city and under about 50MPH will 4th be ok on the vehicle? Also how does driving in 4th affect MPG?
     
  4. Mar 25, 2009 at 1:30 PM
    #4
    RockDoc

    RockDoc Member

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    I can only speak from personal experience and from my limited knowledge. As far as I know, having a 5 speed auto tranny makes D a little crazy for in town driving. As in, thats too many gears. I dont think driving in 4 will hurt anything as long as you dont get the rpm's too high. As far as mpg, I have consistantly been getting 18, but that is in hilly terrain at various speeds, so I consider that to be pretty good. Maybe some other guys with more knowledge and experience will take a look at this thread and reply. I switched from a '95 4runner to the Tacoma, and have noticed all kinds of different things. Lower idle rpm, lower shift rpm, etc., but it all seems pretty normal. I think this engine/tranny setup is meant to do everything at lower rpm's. Anyone else want to chime in? Anyway, good luck, enjoy your new truck...
     
  5. May 1, 2009 at 10:24 PM
    #5
    San Mig

    San Mig Member

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    Please enlighten me about Auto Braking System in Auto Transmission.
     
  6. May 2, 2009 at 4:35 PM
    #6
    San Mig

    San Mig Member

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    Is that normal to all Tacoma trucks,if that so it also consumes gas as it is using engine brake.Thanks for the info.
     
  7. May 2, 2009 at 4:42 PM
    #7
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    When "engine braking" the fuel injectors are "Off", until below 1200 rpm, so there is no more use in fuel than if you were doing the same in a manual tranny.

    FWIW, The tranny is simply behaveing like a manual, as it was programmed to do. Most auto trannies will unlock the torque converter, thus "coasting", when the throttle is let off. The Toyota 5 speed auto is programmed to keep the converter locked, thus provideing engine brakeing when the throttle is let off. Rason its not felt as much in 4th gear, is it may be in a "semi" lock position (as it has the capability to be fully unlocked, locked, or anything in between). When in 5th (D), and you let off the throttle, it is fully locked, therefore you feel a more rapid deceleration.
     
  8. May 3, 2009 at 4:54 PM
    #8
    San Mig

    San Mig Member

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    Double Din DVD Player with i-pod interface, Chrome Step Tube, Bed Extender,Door Sill Protector.
    That's what I feel,it decelerates rapidly, you have to press the gas pedal heavily to gain back the momentum.I used to have a First Generation '04 model and its not doing that"auto braking" although it's only 4 speed. I grew up around Toyota Cars and Trucks and that is why I still own one. Even this one consumes more Gas than the previous Generation.

    Thank you and more power to all.:cheers:
     
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