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

LSD .. ALSD .. WTF

Discussion in '2nd Gen. Tacomas (2005-2015)' started by sgtpepper, Mar 23, 2011.

  1. Mar 23, 2011 at 3:35 PM
    #1
    sgtpepper

    sgtpepper [OP] Active Member

    Joined:
    Mar 13, 2011
    Member:
    #52971
    Messages:
    36
    Gender:
    Male
    this is a bit of a noob question, so feel free to flame
    in my defense, I searched, I read, it gave me a headache. so here we are

    I was told my 2010 Sport has ALSD (I bought it used from a non-toyota dealer and the salesperson couldnt tell me much)

    Now I know what a normal Limited Slip is all about, but wtf is an ALSD? is there even such thing as ALSD? did the dude just make it up to sound special?

    Really all I need to know is do I need the LSD additive when I change my rear diff oil?

    ps. This truck isnt going off road any time soon, maybe in a few years it'll get real lockers. for now I still have the Jeep (built & lifted) for the weekend wheeling activities.
     
  2. Mar 23, 2011 at 3:40 PM
    #2
    brutalguyracing

    brutalguyracing BIG DADDY

    Joined:
    Jun 28, 2009
    Member:
    #19000
    Messages:
    24,038
    Gender:
    Male
    F.U> GUYZ
    broken mods
    there should be a sticker on your rear diff that state what to use....
    that being said... i do belive yours needs the additive,,,,,,
     
  3. Mar 23, 2011 at 3:52 PM
    #3
    Leggo

    Leggo slow is smooth, and smooth is fast.

    Joined:
    Dec 16, 2010
    Member:
    #47805
    Messages:
    2,420
    Gender:
    Male
    First Name:
    Steve
    Newton,Ma.
    Vehicle:
    10 TRD Sport AC 4x4 MGM
    Kenwood HU,Infinity Kappa speakers (x4), Infinity reference tweeters(x2),10" Kicker sub, Box by Subthump, Infinty Five channel amp,DVD anytime bypass, DTRL Mod, Xtang trifecta, Fogs anytime Mod, Bed Mat,Westin running boards, Console vault, Maglite mod, Weathertechs,Autopage remote starter, Power tailgate lock, HID Bi Zenon, Hella Supertones,Rain guards,Rear leaf TSB,Steering shaft TSB, Fisher Homesteader plow, 886 reverse lights mod, Redline Hood struts, Hankook Dynapro ATM LT265/70R17, power sliding rear window, Auto dimming/on anytime Bed lights, Blue Sea fuse panel & 100amp Breaker, de- badged,Rear headrest's removed, imMrYo mirror relocation,Homeroshi grill
    The ALSD is simply a computer that cycles the brake on the wheel that is slipping causing the wheel that is gripping to get some drive. It uses the speed sensors to detect what is going on and what needs to happen from there. I am thinking you do NOT have LSD in the mechanical sense. It's ok, everything is going to be alright. Look for the sticker on the diff itself. If no sticker, no additive. Goodluck and stay thirsty my friend
     
  4. Mar 23, 2011 at 9:52 PM
    #4
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags
    No, 2009+ Tacomas do not have a special differential that requires special lube... They are all open differentials and the limited slip is created by sensors and the brake system... Here is how to go from standard mode limited slip 'TRAC' to stronger limited slip 'AUTO LSD' or to turn the limited slip off 'VSC OFF MODE':

    [​IMG]
     
  5. Mar 24, 2011 at 8:19 AM
    #5
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags
    New technology is nothing to fear...

    The goal of "limited slip" is to slow a non-traction/free spinning tire so the torque power can be shared more with the non-spinning tire with traction... so the truck will move ahead.

    Rather the slowing of a spinning tire is done inside the differential with clutches or on the wheel itself with brake pads, the same result is created.

    Now, what is cheaper to replace: brake pads or the insides of a differential ??? :rolleyes::eek::D Good Toyota!
     
  6. Mar 24, 2011 at 8:22 AM
    #6
    fvtalon

    fvtalon Well-Known Member

    Joined:
    Aug 12, 2010
    Member:
    #41625
    Messages:
    234
    Gender:
    Male
    First Name:
    Mike
    Southern BC
    Vehicle:
    07 DC TRD/Yamaha
    285/65/18 BFG ATs on MKWs Leer Cap
    Yeah, basically the ALSD is a way to use the braking system to get LSD like action out of an open diff.

    There's a strange quirk with a regular open dif where the input torque gets split basically 50/50 to each tire as long as both tires have equal grip. But when the grip is unequal, gravel on one side, pavement on the other, one side icy, etc, the open dif transfers power to the wheel that slips. The wheel with the least traction gets the most power. So normally you'd have to add some kind of geared or clutched unit inside the differential to overcome this effect and keep power going to both wheels.

    The mid 90's introduction of the M-class Mercedes SUV is the first time I remember reading about the ALSD where the car's computer can use the ABS wheel speed sensors to monitor the relative speeds of the wheels and determine slippage. Then it can activate the brakes via the 4 channel ABS in order to brake any one wheel or as many as necessary in order to transfer power to the wheel or wheels that have traction. With open front, center and rear difs and 4 channel ALSD you could potentially transfer the bulk of the power to any 1 wheel.
     
  7. Mar 24, 2011 at 8:47 AM
    #7
    MountainEarth

    MountainEarth Well-Known Member

    Joined:
    Feb 1, 2010
    Member:
    #30519
    Messages:
    2,487
    Gender:
    Male
    First Name:
    Bryan
    CO
    Vehicle:
    2010 TRD OR Access
    Leer 100XR Shell, BedRug mat - comfy sleeping, GT Covers microfiber seat covers, BFG All Terrains 265/70r16, Dashmat, Antennax 13" shorty antenna, Weathertech liners, Ultra Gauge, Avid Light Bar, PIAA 520 ATPs, one old dog
    I think it's BS that AutoLSD doesn't work in 4lo because a mechanical LSD does. IMO replacing the mechanical LSD with the electronic ALSD was a step backward in terms of traction control. At least as far as 4lo is concerned.
     
  8. Mar 24, 2011 at 9:08 AM
    #8
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags
    Seems unfair, but Toyota figured if you were going to do serious off roading, then you would get the Off Road Tacoma and not a Sport or Base.

    The Off Road TRD has A-TRAC in L4, which is even stronger than ALSD.
    All other Tacomas (2009+) can perform the 4-Low Trac Mod (yellow wire mod) to get TRAC (ALSD) to work in L4.

    Until then, you have TRAC in H4 (same function as ALSD) and it will outclimb L4 with open differentials.
     
  9. Mar 24, 2011 at 9:08 AM
    #9
    Burgman

    Burgman I KEEEEEL YOU

    Joined:
    Apr 16, 2009
    Member:
    #16072
    Messages:
    26,682
    Gender:
    Male
    First Name:
    Stephen
    Ric VA
    Vehicle:
    08 PreRunner TRD sport Silver
    K&N intake, Boston Acoustic SL 60 6.5 components up front, Rockford Power T16 6.5 in rear, Pioneer P4100 HU, Soon to be Pioneer Prs 4200f
    Mechanical LSD whoops ALSD's ass 9 outta 10 times
     
  10. Mar 24, 2011 at 9:33 AM
    #10
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags
    Now if you had an '09 instead of the '08, I bet you wouldn't say that...

    If you ever need to rebuild your differential, as well...

    It is all about slowing down one side of the differential... it is just cheaper to do it with brakes, that's all. :)
     
  11. Mar 24, 2011 at 9:38 AM
    #11
    Burgman

    Burgman I KEEEEEL YOU

    Joined:
    Apr 16, 2009
    Member:
    #16072
    Messages:
    26,682
    Gender:
    Male
    First Name:
    Stephen
    Ric VA
    Vehicle:
    08 PreRunner TRD sport Silver
    K&N intake, Boston Acoustic SL 60 6.5 components up front, Rockford Power T16 6.5 in rear, Pioneer P4100 HU, Soon to be Pioneer Prs 4200f
    well ive seen my mechanical lsd lockup in places where the ALSD wouldnt, that is all
     
  12. Mar 24, 2011 at 9:49 AM
    #12
    Burgman

    Burgman I KEEEEEL YOU

    Joined:
    Apr 16, 2009
    Member:
    #16072
    Messages:
    26,682
    Gender:
    Male
    First Name:
    Stephen
    Ric VA
    Vehicle:
    08 PreRunner TRD sport Silver
    K&N intake, Boston Acoustic SL 60 6.5 components up front, Rockford Power T16 6.5 in rear, Pioneer P4100 HU, Soon to be Pioneer Prs 4200f
    like i said ive been offroading with people running the Mechanical LSD and others with the ALSD and when the rear tires would articulate the mechanical LSDs would lock up and pull through better than the ALSD
     
  13. Mar 24, 2011 at 9:55 AM
    #13
    Burgman

    Burgman I KEEEEEL YOU

    Joined:
    Apr 16, 2009
    Member:
    #16072
    Messages:
    26,682
    Gender:
    Male
    First Name:
    Stephen
    Ric VA
    Vehicle:
    08 PreRunner TRD sport Silver
    K&N intake, Boston Acoustic SL 60 6.5 components up front, Rockford Power T16 6.5 in rear, Pioneer P4100 HU, Soon to be Pioneer Prs 4200f
    im thinking i got through places in 2wd where the ALSD had to put it in four and still had problems... my experience is that the mechanical locks up better
     
  14. Mar 24, 2011 at 5:48 PM
    #14
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags

    Thank you for being civil and clearly quoting each part of my reply to contend... good job!

    Now, let me just end with: Tacomas do not come with limited slip differentials anymore (after a brief 4 year use of them on SPORT TRDs only)... they all now have traction control. So, either learn to like it like those of us who do, or spend $$$ with after market stuff.
     
  15. Mar 25, 2011 at 7:41 AM
    #15
    tmacbigbass

    tmacbigbass Member

    Joined:
    Jan 17, 2011
    Member:
    #49411
    Messages:
    6
    Gender:
    Male
    Vehicle:
    09 Prerunner
    For slick roads can you leave the ALSD on while driving at speeds of 30 MPH or slower or do you need to leave it off until you start spinning.
     
  16. Mar 25, 2011 at 8:19 AM
    #16
    David K

    David K Well-Known Member

    Joined:
    Jun 27, 2009
    Member:
    #18969
    Messages:
    9,932
    Gender:
    Male
    San Marcos, Alta California
    Vehicle:
    2010 4WD Off Road DC
    Differential Breather Mod Light Bar: 2 Hella 4000 HID, 1 Cibie Halogen. Bilstein 5100s Ride Rite Air Bags
    Good question... since it seems designed to help you get moving from a stuck/start. If you are in town on icy roads with a lot of stops and starts where you need the AUTO LSD, might as well leave it on. The VSC automatically re-activates at 30 mph, so I don't know of a reason to shut off ALSD for higher speed skid control?

    There is a concern mentioned in the manual about over using the brakes, but as 4WD-HI is using the same feature (TRAC without engine regulation) and no mention of 'over-using' is there, I would like to hear a tech say what the difference is with ALSD in H2.

    I suppose if there is no need for ALSD, just let TRAC do its thing in H2... but on icy or slippery roads, keep it in ALSD.
     
To Top