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

Just a NOTE:

I made this thread to help us with knowing what are the NINE (then) traction choices of the OFF ROAD 4WD TRD. That applied to 2009-2011 trucks.

In 2012, Toyota added a 10th mode (in H4: 'TRAC OFF', as an optional push button choice and made TRAC in H4 an engine regulated mode, like it is in H2).

I made a new thread for 2012+ Tacomas, but that one was either closed or is buried somewhere and this 2009-2011 thread continues to live on.

I am happy to continue to help, but as an owner of a 2010 Tacoma, I must rely on feedback from newer owners to accurately tell you what is happening or which one may be best to use.

Just play with your Toy... press and press again the VSC OFF button (Toyota says "switch") in H2 and H4 and note what happens, what lights go on or off, and if things change at 30 mph. This applies to all Tacomas, not just the Off Road TRDs.

Stopping the truck, press and HOLD IN the button for a few seconds should turn OFF both VSC and TRAC for unregulated, open spinning tires... until it senses danger, then will turn VSC back on. NOTE: I don't recommend VSC OFF for any situation, I like having traction control and stability control, your truck goes further!

TRAC OFF does NOT mean that TRAC is turned off!
Just the opposite, TRAC OFF means that engine regulation is turned off.
AUTO LSD is TRAC OFF in H2. AUTO LSD is more limited slip action than standard TRAC because the throttle is not cut, so power will be fully applied to the traction tire.
In H4, 2012+ this is called TRAC OFF (quick press of the button, moving or stopped). 2009-2011 has no button to push, as TRAC has no engine regulation in H4. They just didn't change the name from 2WD TRAC.

It is the names more than anything that confuses people.

1) Use the standard mode first (TRAC).
2) If tire spin occurs, quick press the button (VSC button) for AUTO LSD MODE or if 4WD, select H4.
3) If tire spin occurs in H4, quick press VSC button for the stronger TRAC OFF MODE.
4) If more power, crawling, or climbing needed, use L4. A-TRAC always on, if the Off Road TRD.
5) If A-TRAC fails to keep you moving, use the Rear Differential Locker as an emergency option.

 

This thread?

 

That is one, thank you... I was thinking of another, but I did so many, lol!

 

GREAT thread! Very informative. Thank you!
Not trying to tell you what to do, but suggest updating your signature to include the newer thread, if you want to steer folks to it...

 

I appreciate the comments, Norton. I like my original thread as it has photos of the lights that come on and YouTube links to show what is happening. Until I drive or ride in a 2012 or newer TRD Off Road 4WD, I won't have that media to illustrate. I was really hoping there was a clone of me out there who is as nutty as I am about wanting to know what each drive mode does.

I really need to ride in an MTS truck to see how A-TRAC works coupled to that system... Crawl, too.

 

I'm sure you are aware but just incase and to not confuse people who don't know, MTS is only available with Crawl control which is only available with an automatic. A-TRAC comes on the manuals and is the same settings/functions as on the 2nd gens unless someone can tell me otherwise.

I'm willing to do some testing on a 2017 OR manual if you tell me what you'd like. I haven't done much testing but as far as I can tell the traction system on my truck is the exact same as what you have originally posted expect 4Hi has TRAC OFF now. You pretty much nailed it with the post that was just linked.

 

Thanks. Yes, I know Crawl and MTS are offered as a joint package and only on the automatics. Obviously, on a manual, you can't manipulate the clutch the way you would need to (without risk of stalling).

Thank you for confirming that the VSC button functions remain the same from the 2012 model year. Can you confirm these things, please?:

In H2 (with a quick press= AUTO LSD) is the VSC OFF LIGHT on at 0-30 mph, then goes off over 30 mph? [this is how it is in 2009+ models]

In H4, quick press=TRAC OFF: Is the VSC OFF LIGHT also turned on? If it is on, does it go off at 30 mph+?

In H4, press and hold in while stopped = VSC OFF: is the TRAC OFF light also on?

Photos of the dash lights at each of the 10 modes would duplicate my 2009-2011 model 9 mode description post. I would invite you to make it your own thread, in the Third Gen forum, if you want or here. Thanks !!!

 

Quick question, so when in 4LO when people are doing the eBrake locker trick, that doesn't do anything then right?

 

I'll try and get this done this week sometime.

 

Not sure what you are asking, but I will guess it is using the parking brake to limit wheel spin? If you don't get the OFF ROAD TRD 4WD, then anything is better than nothing... and on all models except the OFF ROAD, you have nothing for added traction in L4. The advantage being only the lower gears.

For non-Off Road 4x4 Tacomas in Low Range to improve traction:
Solution 1: LOWER the air pressure in your tires! It will amaze you what 15 psi can do over 30 psi!
Solution 2: Partially brake the tire if it begins to spin, forces power to the traction tire.
Solution 3: Do the 4-LOW TRAC MOD (Yellow Wire Mod).

 

For non-Off Road 4x4 Tacomas in Low Range to improve traction:
Solution 1: LOWER the air pressure in your tires! It will amaze you what 15 psi can do over 30 psi! - I wheel in 13PSI
Solution 2: Partially brake the tire if it begins to spin, forces power to the traction tire. - This is the eBrake thing I was asking about, Poor mans locker. Put the ebrake on and it makes the power go to the other wheel that is not spinning. Does this work in 4LO?
Solution 3: Do the 4-LOW TRAC MOD (Yellow Wire Mod). - I intend to.

 

4 Lo has more power to turn the wheels, so more brake force needed.
I don't need to use the parking brake because I have A-TRAC and a locking differential.
Sounds like a project for you?

 

Yes a project, but you still haven't answered the question....
when in 4LO when doing the eBrake locker trick does it do anything since nothing is turned on in say a stock Tacoma Sport 4x4?

 

Sorry I wasn't clear, I have never used the eBrake BECAUSE I have A-TRAC and it does the braking automatically and on just the tires that slip. I see no reason that it wouldn't help, it is an old trick.

 

well if normally a-trac is turned off in 4LO then it shouldn't work. Right?

but with the yellow wire mod it will work.

what I'm trying to figure out is if it's really wokring when I am in 4LO and i put the brake on a little, if it's really doing anything or I think it's helping.

 

Sub a dub dub

 

A-TRAC is selectable (on or off) and it only works if there is wheel spin (ie. only when you need it). I naturally always have the A-TRAC in the on mode when in L4. There is NO advantage to not use it. I don't want my tires spinning, because that would mean I have no traction.

The yellow wire mod lets the TRAC system work in L4, that's all. Use the eBrake partially depressed to help slow tire spin, IF you don't have any of the fancy systems. Be warned, you are wearing the brake pads and shoes by using the brakes when there is no spin.

 

I keep hearing about this yellow wire mod. Not sure if I'm going to drink the kool aid on that one. Running SR5 Model has its disadvantages until locker install
And re-gearing. But I'll have to read all 68 pages to figure out if it's worth the hype.

 

This thread is not about that mod... Read the 4Lo Trac Mod thread.
It is for the non-Off Road 4x4s that have nothing in L4.

 

It's all so confusing though