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

AUTO LSD (or Not) for added traction in 2WD?

Discussion in '2nd Gen. Tacomas (2005-2015)' started by David K, Oct 19, 2010.

  1. Oct 19, 2010 at 10:49 PM
    #1
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    Well, with the wet weather upon us, I was wondering if many of you with the 2009 or newer Tacomas (equiped with TRAC and AUTO LSD) have 'two wheeled' using AUTO LSD... which is the limited slip TRAC system without any engine output regulation?

    2WD Tacos (or 4WD Tacos in H2) have THREE traction choices:

    A) TRAC ON (standard mode) 'TRACTION CONTROL' a limited slip with engine regulation.

    B) AUTO LSD or "TRAC OFF MODE" (press the VSC OFF switch to engage) limited slip without any engine regulation.

    C) "VSC OFF MODE" (while stopped, press and hold-in the VSC OFF switch for several seconds) to have an open differential with no TRACTION CONTROL



    [​IMG]

    ToyotaDriveModes-1_fb6bbc2bfd62c6f7514057a58e9345cc0002c14f.jpg

    I have found AUTO LSD to work like a 'Posi-Traction' differential, providing strong torque to both rear tires when both have equal traction. If one tire is on solid ground and the other isn't, then instead of the loose tire spinning, it is braked and torque goes to the traction tire so you can move.

    For those without 4WD, the AUTO LSD is the next best thing to having a locking rear differential to help you move.

    Have you used AUTO LSD, and what did you discover?
     
  2. Oct 19, 2010 at 10:54 PM
    #2
    Jefenator

    Jefenator Taco Truck Noob

    Joined:
    Sep 16, 2010
    Member:
    #43328
    Messages:
    147
    Gender:
    Male
    Oregon
    Vehicle:
    2010 2WD Reg Cab Stick Shift
    Sub'd. (Too lazy to do my own testing. :rolleyes:)
     
  3. Oct 19, 2010 at 10:58 PM
    #3
    OZ-T

    OZ-T You are going backwards

    Joined:
    Dec 15, 2009
    Member:
    #27584
    Messages:
    50,399
    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
    It's difficult for me to accept Auto-LSD .

    ( j/k subbed for info )
     
  4. Oct 19, 2010 at 11:02 PM
    #4
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    Very funny! I figured we beat that dead horse (why A-TRAC) enough LOL!
     
  5. Oct 19, 2010 at 11:03 PM
    #5
    OZ-T

    OZ-T You are going backwards

    Joined:
    Dec 15, 2009
    Member:
    #27584
    Messages:
    50,399
    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
    :D haha
     
  6. Oct 19, 2010 at 11:55 PM
    #6
    Pyrite FD

    Pyrite FD Well-Known Member

    Joined:
    Oct 14, 2009
    Member:
    #24330
    Messages:
    92
    Gender:
    Male
    Indiana
    Vehicle:
    09 DC TRD Off Road
    wish it didnt cut off over 35 :(
     
  7. Oct 20, 2010 at 4:49 AM
    #7
    myname150

    myname150 Well-Known Member

    Joined:
    Jul 5, 2010
    Member:
    #39827
    Messages:
    1,350
    Gender:
    Male
    Has anyone ever tried using the parking brake (for those with out a LSD or a rear diff lock)...?

    Pretty much when you start getting wheel spin in the back, set your parking brake enough to grab so both tires will spin at the same speed and slowly apply gas. I dunno if its any good for your drums though.
     
  8. Oct 20, 2010 at 5:44 AM
    #8
    tacobox

    tacobox Evasive Maneuvers PMKMS

    Joined:
    May 9, 2010
    Member:
    #36834
    Messages:
    596
    Gender:
    Male
    I don't think that'll work though I see you concept. Both rear wheels whould have brake pressure on them and one will still be on a slippy surface while the other has traction. The power would still follow the path of least resistance (the slippy wheel). Now if ya had indevidual brake control to each right a left rear wheels it "might" be a different story.
     
  9. Oct 20, 2010 at 8:17 AM
    #9
    myname150

    myname150 Well-Known Member

    Joined:
    Jul 5, 2010
    Member:
    #39827
    Messages:
    1,350
    Gender:
    Male
    Wait, wouldnt there be brake pressure if the parking brake is applied or some sort of "braking"?
     
  10. Oct 20, 2010 at 8:55 AM
    #10
    tacobox

    tacobox Evasive Maneuvers PMKMS

    Joined:
    May 9, 2010
    Member:
    #36834
    Messages:
    596
    Gender:
    Male
    No the e-brake is mechanical, incase of a brake pressure malfunction.
     
  11. Oct 20, 2010 at 8:59 AM
    #11
    trd09

    trd09 Well-Known Member

    Joined:
    Jul 20, 2009
    Member:
    #19899
    Messages:
    360
    Gender:
    Male
    First Name:
    Chuck
    NW Ark
    Vehicle:
    17 TRD Pro 6AT
    Have thoroughly tested ALSD and yes, it works but requires a decent amount of gas to be effective.

    And with one wheel in the air, it is not nearly as effective as a locker. If there is a decent obstacle in front of the wheel on the ground (ie a rock or a hill), it does not transfer power well enough to get over it...
     
  12. Oct 20, 2010 at 9:06 AM
    #12
    NAYo2002

    NAYo2002 Well-Known Member

    Joined:
    Jan 16, 2009
    Member:
    #12655
    Messages:
    485
    Gender:
    Male
    Great Falls, MT
    Vehicle:
    '09 Tacoma 4x4 TRD Off Road
    Michelin LTX A/T2, TRD Skid Plate, WeatherTech DigiFit Liners, OEM Bed Extender, OEM Bed mat, Advantage TorzaTop Trifold Tonneau, Pop & Lock PL5300
    I've never been able to test out A-LSD. I tried it last winter but it didn't do anything for me (prob both tires were on ice.) That said, I always switch to 4x4 since it's just less hassle than trying to find out if only one or both tires are spinning. I'll remember to try again when the opportunity presents itself though.

    Here's a thread on comparing Auto LSD to Mech LSD:

    http://www.tacomaworld.com/forum/2nd-gen-tacomas/81272-mechanical-lsd-vs-auto-lsd.html
     
  13. Oct 20, 2010 at 9:26 AM
    #13
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    Getting some good replies... On the 35 mph cut off reply, perhaps the logic there is if you are able to go more than 35 mph, there is no need for AUTO LSD, since you were able to get moving from a stuck? At speed it is safer to have open differentials for steering ability... locked differentials are difficult to steer and could be a danger at speed (why the max. 5 mph warning on the rear locker use).

    I found this on the Internet, from a Tundra discussion... but it applies to our Tacomas, too:

    Why Auto LSD is more effective than Standard LSD Differentials

    Posted on 26. Mar, 2009 by TJ Houghton in Toyota, Toyota Stuff, Toyota Truck, Toyota Tundra Brakes, Tundra

    Auto LSD Review – Advanced brake controls give Tundra drivers options in solving traction problems.

    Auto LSD provides substantial benefits over mechanical LSD; that is, it improves traction by reducing wheel spin on slippery surfaces just like standard LSD rear ends, but Mechanical LSD needs some type of friction mechanism or gear arrangement in the differential, which can be noisy or generate other discomforts. Auto LSD works with an open differential that is quieter and smoother. Mechanical LSD may be less effective over time (wears out), plus can only transfer approximately 25% of available power to the wheel with traction whereas Toyota’s Auto LSD can transfer up to 100%! That is why the Tundra can go places in 2-Wheel Drive the competition can’t.

    Automatic Limited Slip Differential (Auto LSD) is a unique feature on the Tundra that the driver must engage. It is not an automatic on/off function, as the name may imply. On the Tundra, Auto LSD is engaged by pushing the dash-mounted VSC Off switch.

    In a recent media shootout between ½-ton pickups, the test drivers climbed a 20-degree incline with trucks’ right- and left-side wheels on either dry asphalt or wet basalt tile, which can simulate snow and provide a relatively consistent traction coefficient for a comparison test. While the Tundra was one of only two trucks to reach the top without shifting into 4-wheel-drive, it wasn’t the fastest. And the test driver complained that engine power was reduced too often. The driver didn’t engage Auto LSD, which would have allowed a more aggressive response.

    TRAC is the Tundra’s default traction-control feature. Both TRAC and Auto LSD work in a similar manner. When the system detects a spinning the wheel on the rear axle, the brake is applied to that wheel. By slowing down the slipping wheel, power is transferred to the opposite wheel with more traction. TRAC also reduces engine power to help eliminate wheel spin. TRAC is an intergral part of Toyota’s Star Safety System.

    In some situations, more engine power and a little wheel spin are needed, especially when off-roading. With Auto LSD, the system doesn’t reduce engine power as much* and allows a limited about of wheel spin to the wheel with the most traction. This helps the driver “dig” out of certain conditions such as deep sand or mud, and maintain momentum up a slippery hill.

    When the driver pushes the VSC Off switch once, TRAC is turned off and Auto LSD is engaged. The VSC Off switch is also used to turn off VSC, if the driver chooses. There is a specific sequence involving pushing and holding the VSC Off switch to achieve the desired setting between the different modes. This sequence has changed between model years, so drivers must consult their owner’s manual for details specific to their Tundra.

    [*in the Tacoma, no engine power is reduced]
     
  14. Oct 20, 2010 at 9:32 AM
    #14
    trd09

    trd09 Well-Known Member

    Joined:
    Jul 20, 2009
    Member:
    #19899
    Messages:
    360
    Gender:
    Male
    First Name:
    Chuck
    NW Ark
    Vehicle:
    17 TRD Pro 6AT
    no chance. the wheel spinning never stops spinning with ALSD, therefore not nearly 100% of the power is transfered.

    perhaps 100% of power can be transfered with ATRAC, but no way with just alsd
     
  15. Oct 20, 2010 at 9:39 AM
    #15
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    No chance of what?

    Not sure what you are trying to find out or say... and ATRAC is not available on 2WD Tacomas...

    Here is the name of this thread:

    AUTO LSD (or Not) for added traction in 2WD?
     
  16. Oct 20, 2010 at 9:48 AM
    #16
    trd09

    trd09 Well-Known Member

    Joined:
    Jul 20, 2009
    Member:
    #19899
    Messages:
    360
    Gender:
    Male
    First Name:
    Chuck
    NW Ark
    Vehicle:
    17 TRD Pro 6AT
    No chance that ALSD transfers 100% of power (I bolded the part of the post that I was responding to)

    The only electronic aid that is able to transfer power near 100% is ATRAC, which is not available on 2WD as you said. Much of the thread is discussion electronic aids vs. mechanical, sorry if it was confusing....

    I am aware of the thread title. No reason to get aggressive here.....
     
  17. Oct 20, 2010 at 9:50 AM
    #17
    BlueT

    BlueT Well-Known Member

    Joined:
    Mar 30, 2009
    Member:
    #15341
    Messages:
    5,615
    Gender:
    Male
    NorthEast
    Vehicle:
    07 Dbl Cab LB with LSD
    I moded 1999 Taco so much it had turned to Land Cruiser
    images_96954fdd26752a648f892d83c96dd624e3240e3c.jpg images_385fbbbebef0eee36ccb81e73895313e9e9c7b55.jpg images_11574bf5a7a7317310c96bfa4f4185d5e590e0a7.jpg images_9fe3f346bed28a55c0625be9a168482fd1833060.jpg images_aed40d586c78c7a0a9d1e3a703d0ee7201ebc6db.jpg images_be292d64f5a01433adb0a2b28167f480699f9221.jpg
     
  18. Oct 20, 2010 at 12:57 PM
    #18
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    Blue, isn't that 5 mph warning plastered in your Taco and in your owner's manuel? No such warning on using AUTO LSD (or A-TRAC)... why is that, you suppose? Could it be that those traction systems don't affect steering???

    Please stay on topic: AUTO LSD... Do you have ANY experience using it... at all???
     
  19. Oct 20, 2010 at 12:59 PM
    #19
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    No aggression intended, I am sorry if you took it that way or if it sounded that way from me!

    Is 100% power transfer needed, if (as you say) the AUTO LSD doesn't give that?
     
  20. Oct 20, 2010 at 1:36 PM
    #20
    David K

    David K [OP] Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    12,350
    Gender:
    Male
    Pala Mesa, California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 4 Cree LED lamps Bilstein 5100s Ride Rite Air Bags
    Auto Limited Slip Differential (Auto LSD) -- Auto LSD uses the TRAC system to achieve the capability of a Limited Slip Differential (LSD) when driving in 2WD mode. (On a 4WD vehicle, Auto LSD only operates when the vehicle is being driven in 2WD mode.) Because Auto LSD and Rear Differential Lock perform similar functions, vehicles may have one system or the other, but not both. While Auto LSD components are similar to those in the TRAC system, there are important differences.
    ----------------------------------------------------------------------

    The standard Automatic Limited-Slip Differential (Auto-LSD) helps provide better acceleration in deep sand or mud and on mixed-friction surfaces. Compared to a conventional mechanical limited slip differential, the Auto-LSD system is much more responsive and has better wear characteristics.
     

Products Discussed in

To Top