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A-TRAC/TRAC/AUTO LSD Explained (Easy to understand, I hope!)

Discussion in 'Technical Chat' started by David K, Jan 19, 2010.

  1. Sep 16, 2013 at 5:02 PM
    #1361
    MonkeyProof

    MonkeyProof Power Top

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    Is it really that hard to press a button? Does your finger cramp up just thinking about it like mine does? It takes more steps for me to engage or disengage my rear locker then it does to do the same for my front locker.

    :popcorn:
     
  2. Sep 16, 2013 at 5:03 PM
    #1362
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Thor

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    No cramps yet, but I haven't pushed it hard.
     
  3. Sep 16, 2013 at 5:04 PM
    #1363
    OZ-T

    OZ-T All of those moments....will be lost.....in time

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    Damn , this pissing match is still going ?

    Locker ~ push button
    ATRAC ~ push button


    anyways , carry on
     
  4. Sep 17, 2013 at 9:01 AM
    #1364
    David K

    David K [OP] Well-Known Member

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    Thanks Paul... I know you gave a fair test when you added the front locker to your A-TRAC Tacoma... and because a locker doesn't allow any slippage, it is a smoother traction choice when you need it on the front. However, as you were with me on the Mission Santa Maria run, and I only used A-TRAC and not the rear locker once... you must agree that it works and gets a stock Tacoma through places where lockers would normally be needed: the widowmaker and the bog. It was Art with front and rear ARB lockers that told me the A-TRAC was better since it was like 'automatic lockers' that allowed the tight turns be made on the granite rock roadbed.
     
  5. Sep 17, 2013 at 4:45 PM
    #1365
    HBMurphy

    HBMurphy Ban Pending

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    NP - My point was their is a 'World' of people out there that have a Toyota product that is equiped with this type of traction control. 99.99% of them will never contemplate a buying a locker. For those that will, this thread is for nothing other than trolling for entertainment.

    For the other 99.99% you have done a great job of explaining it. Something that few would do. That's all.

    I will say, I have done years of trolling so I recognize it when I see it. Keep educating those that aren't in that club. :)
     
  6. Sep 18, 2013 at 5:42 AM
    #1366
    Brandon H

    Brandon H Well-Known Member

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    I will give credit to David for a fantastic thread on ATRAC. You bet. he has done an excellent job on explaining the atrac system. The reason the "rest of us" (apparently the 1% club :rolleyes:) became involved is when he started saying that atrac is better than having a locker. There is 2 toyota 4wd vehicles in my family (one is an FJ Cruiser with A-Trac, the other is a tacoma with front and rear lockers). I have experienced the tractions systems of both of these vehicles long before he has even had an atrac equipped vehicle (FJ is an 07). Although the Atrac system is adequate at best (computer system that pulses the brakes when it senses slippage), it is nowhere a suitable substitute. Thats all it does. It dosent "lock" anything. With that being said, it is a great standard feature for stock tacomas. I guess we are trying to educate those who are interested in buying a 4wd tacoma who are looking for something more than "light" off roading, the best bet is to get a base model 4x4 and add f/r lockers. in the long run, you will save a signifigant amount of money over the price of a TRD Off road. Most of the TRD offroad "add-ons" are going to be replaced anyway by aftermarket suspension, tures, wheels, etc. so why waste your money on an overpriced TRD Offroad? FOr those who want to keep it stock or lease the vehicle and have no choice, get the offroad package. But please dont say atrac is better, because its not. OP has never even driven a vehicle with a front locker, so how can he make a valid statement like that??
     
    Last edited: Sep 18, 2013
  7. Sep 18, 2013 at 7:03 AM
    #1367
    MonkeyProof

    MonkeyProof Power Top

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    Damn brandon, why you up so early?
     
  8. Sep 18, 2013 at 7:07 AM
    #1368
    SoCaltaco65

    SoCaltaco65 Well-Known Member

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    And the Saga continues....

    I like choices, A-TRAC has its place, no doubt, but when that lil extra positive grip is needed the front locker sure makes it nice..

    I regularly go to Finger YOGA, helps with the finger cramps...
     
  9. Sep 18, 2013 at 8:19 AM
    #1369
    Brandon H

    Brandon H Well-Known Member

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    Been at work since 5. Working 4 10s this week to go to pismo :D
     
  10. Sep 18, 2013 at 9:34 AM
    #1370
    Manwithoutaplan

    Manwithoutaplan the full Monty

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    Brandon you should gather some sand in mason jar give it to Tom for present since he love's sand so much.
     
  11. Sep 18, 2013 at 10:00 AM
    #1371
    Brandon H

    Brandon H Well-Known Member

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    :D:D:D
     
  12. Sep 19, 2013 at 12:13 AM
    #1372
    David K

    David K [OP] Well-Known Member

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    If I came across to some of you as putting down front lockers, I am sorry... I have tried many times to make it clear that I am talking about what Toyota gives us with the Off Road, and how much more secure it is off road than anything else from the factory. If you can afford the aftermarket front locker and do that extreme type of off roading, great.

    This A-TRAC Tacoma is a 'level' or even a 'world' above my previous Off Road 4WD Tacomas ('01, '05) in traction, and more... I don't fear getting stuck (not that getting stuck was a problem before, but it happened briefly a few times), and I easily pull others out of trouble with my 2010.

    I just want folks to know they will really be hard pressed to find a more 'off road' able STOCK Tacoma... and should see if their off roading requirements are not met with the A-TRAC before sinking thousands more into after-market systems. The truck is amazing right from the showroom floor.

    Lifts, bigger/ better tires, front lockers, better suspension are all great things, but not mandatory for a lot of Tacoma drivers... but there's nothing wrong with them!

    The Mission Santa Maria run is a darn good test of traction and durability... you will get rock damage, and you must have a locker, traction control, or extra ground clearance to insure you get through and back out. My 3, pure stock Tacomas all have been to the mission and all three got some damage, but made it in and out on their own. The 2010 trip was the most difficult of the 4 times I been over that road and the one Toyota without a locker or traction aid, required being pulled through the bog. One other Tacoma blew its differential and had to be pulled back out. My 2010 with A-TRAC was amazing and other than the bumper being pulled almost off and some rocks making noise in my front wheels briefly (Paul checked that), I had no issues with the drive.

    From the sound of it, A-TRAC has gone through some generation changes since it was first applied on Toyota and Lexus vehicles (2001?). My A-TRAC does not 'pulse' the brakes and you can see videos of the tires on each axle rotating the same (one in the air and one on the ground), when A-TRAC is working... It does not stay 'locked', so steering is not an issue (on solid ground), but it re-locks quickly if slippage is detected. It is this brief release and re-locking of the tires and the strange noises that makes A-TRAC seem less smooth than lockers and takes more effort or time to negotiate a low traction section of trail... BUT, it is already on the (Off Road 4WD) truck for no extra cost.... IMO, getting further off road is better served by bigger tires and added ground clearance as the first place to spend extra dollars.

    Finally, it was Art, who custom built the 4WD van/ motorhome with front and rear ARB lockers, who told me (after seeing how my truck did), that A-TRAC was better than lockers... my reply was "really?" and I think it was because the Santa Maria trail requires low range and lockers (or A-TRAC) for so long, it was becoming a chore for him to constantly deactivate his lockers due to the many sharp turns on that all rock road. The A-TRAC is like an automatic locker on the front and rear. Just leave it on and it works only when you loose traction.
     
  13. Sep 19, 2013 at 11:13 AM
    #1373
    hellsbay

    hellsbay Well-Known Member

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    Thank you David K. for the excellent post. Finally, I have a clear picture of what I have in my 2013 DC TRD OR in the way of gear and drive selections. Not sure why some are making a pissing contest about front lockers. I am pretty sure that less than .01% of Taco owners would spend the money for this and it should probably have a thread of it's own.

    I'm just sayin'..., :D
     
  14. Sep 23, 2013 at 9:10 AM
    #1374
    Mademan925

    Mademan925 Senor Taco

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    enough to go over stuff
    I read through about 12 pages of this but didnt find an answer for a situation like this. There is a large dirt hill by me that few trucks make it up. Its a steep grade that goes on for about 200 yards. Most people start the hill at about 30 miles and hour and then lose all ther momentum half way up and have to back down in reverse. once you lose your momentum you are relying on the trucks systems. How should I approach a hill like this in my 4x4 trd offroad? 4hi, 4 lo, atrac on?
     
    Last edited: Sep 23, 2013
  15. Sep 23, 2013 at 2:00 PM
    #1375
    David K

    David K [OP] Well-Known Member

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    I would make two runs and compare...

    1) L4, A-TRAC ON... No run, just climb... Having 4WD Low Range is to avoid the need for momentum and breaking parts because of speed (unless this is a smooth surface).

    2) L4, A-TRAC ON + REAR LOCKER ON... if #1 didn't get you to the top, try this. With the rear locked, wheel spin (on the rear) is not limited... Let us know how it goes.

    3) For fun, and to see how TRAC works in H4, do an H4 run (if a newer model with the TRAC OFF mode, use that, if 2011 or older, the standard H4 mode (TRAC).
     
  16. Sep 23, 2013 at 3:19 PM
    #1376
    Mademan925

    Mademan925 Senor Taco

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    enough to go over stuff
    Will do. How fast can I start the hill in L4 with Atrac on?
     
  17. Sep 23, 2013 at 6:21 PM
    #1377
    HBMurphy

    HBMurphy Ban Pending

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    You can always take them all off and get some wheel spin to warm up the tires - then go for it. :)
     
  18. Sep 25, 2013 at 8:12 AM
    #1378
    David K

    David K [OP] Well-Known Member

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    The whole idea of 4WD and specially Low Range is not speed... Speed damages things... Being able to crawl over rocks and up grades without speed or wheel spin (that damages roads and tires) is the benefit of 4WD and Low Range.

    It is 2WDs that need momentum to get past a limiter. The gearing in Low Range will not allow much speed, maybe 30 mph? Use the traction systems, horsepower, good tire tread, and lower air pressure to climb and not speed!
     
  19. Sep 25, 2013 at 8:43 AM
    #1379
    PBR Streetgang

    PBR Streetgang Well-Known Member

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    Take some video for us when you do it, including which mode you are in for each climb. That would be really cool. And maybe some footage of other trucks trying too.
     
  20. Sep 25, 2013 at 12:07 PM
    #1380
    Brandon H

    Brandon H Well-Known Member

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    About 15 mph is about all that can be had out of 4lo. The gearing will be whining out by that point
     
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