A-trac in 4lo on all 2016 4x4 Models Non Trd Offroad

What are the sensors used in algorithms to determine if VSC needs to take corrective action?

 

I would assume all of the sensors are used for VSC

 

The correct answer is steering wheel angle, there is an encoder on the steering wheel, wheel speed from sensors on each individual wheel, speed, gear, throttle setting and yaw rate. There are a lot more sensors but those are used to determine if the vehicle is going where it is being steered and if not take corrective action. I'm not asking any question as you do not understand the difference in these systems and generically consider them all "traction control". Traction control is limiting wheel spin under acceleration, done by cutting throttle and if extreme, apply brakes to the driving wheels. All vehicles that have some form of stability control have a yaw rate sensor that measures the rate of change in direction.

 

Atrac is a dedicated button in the Manual trd OR. No other vehicle has atrac. It functions in 4low and will treat the axles as off they had agressive limited slips front and rear. If you lock the rear, it will work the front axles. The auto lsd feature works in 2 and 4 high and only works rear rear axles lsd feature.

If you hold the trac button in. It will turn off TRAC and auto lsd. Vsc stays on in the back ground unless in 4 low because the abs light is on then, to remind you nothing is there to control the truck unless you put atrac on etc.


Just my observations from a TRD OR 6MT owner who has actually wheeled my truck.

 

If you look at your dash, it will tell you exactly what's going on by which lights are on

 

A lot of us have four wheeled regular and often, previous FJ, present gen 1 TRD and Gen 3 TRD auto OR; and most other brands previously for the past 50 years. ATRAC and auto lsd are electronic simulators of mechanical lsd using ABS technology to slow a spinning wheel which applies torque to the opposite axle, actually somewhat better then a mechanical lsd, depending on the amount of slip built in to the mechanics. The down side is the electronic controls will wear and heat up brakes when actively preventing wheel slip.

 

So, what does a non-OR Tacoma have? LS or ALS?

Nevermind, I found the answer....

 

I coudn't find a good vid of a-trac, but here's a wrangler with 'brake lock differential', basically the same principal. Open diffs, but a slipping tire gets brakes applied and power is therefore, by the nature of an open diff, diverted to the opposite tire with traction.

 

Yeah, best of both worlds; an open differential on the road and electronic limited slip when needed.

 

I'm well aware what it is. I was just explaining how and when

 

https://youtu.be/Vi0y7F4u2R0

 

https://youtu.be/0IUfFdMDaW4

 

https://www.tacomaworld.com/threads/a-trac-trac-auto-lsd-explained-easy-to-understand-i-hope.70551/

 

He was writing to me. He thinks I'm the idiot

 

I'll admit, I thought my truck had a limited slip differential. Now that I've figured out what Toyota calls a LSD, I kinda wish I'd have bought an OR. That being said, I'll likely wait till ARB releases a locker for this truck.

 

I think they have only called it an Auto Limited Slip Differential in all of their paperwork and advertisements

 

Some of you got it right...
Some are not paying attention...

A-TRAC has a hydraulic brake booster.
MTS (adjustable A-TRAC for 2016 automatics) should as well.

Auto LSD is H2 and TRAC OFF is H4, are the names for the same type of traction control. No engine output regulation.

TRAC is traction control (uses brakes and engine regulation in H2 and since 2012 in H4) and traction control is limited slip.

VSC is stability control not traction control.

 

I think on a TRD OR ( auto Trans), when you shift to 4Hi, the Trac Off light is NOT on. That tells me the default is the brake-application LSD is there. If you depress the button that puts it in Auto LSD (2WD only), then while in 4 Hi you have open diffs. When you shift to 4 Lo the Trac Off light is ON. Default is open diffs. To engage "traction control via braking spinning wheel" you must depress the MTS button and select one of the 5 wheel spin algorithms. So in summary you can get open diffs in 4 Hi or 4 Lo but default is in 4 Hi only. I also infer that since you can't select the 5 different levels of permitted wheel spin in 4 Hi, you get the same algorithm that is provided in Auto LSD in 2WD. MTS is not available in 4 Hi. If someone on here knows of something I said that is wrong, pls chime in. There is some mystery surrounding how these systems work since Toyota is not too specific about the details in the Owners Manual; buts and pieces. If you have a manual transmission the A-Trac button and logic applies. A-Trac is not on auto Trans models.

 

This is my first post, as a long time jeep and Toyota offroad enthusiast.
I bought my first new vehicle, a 2017 5 speed Tacoma sr, 2.7l 4x4 this week, and have already done some wheeling in it.(like a moron, lol)

I had read that (on the '09-'15 models, not much info on the new ones) that these trucks (even the base models) have traction control in 2hi and 4hi, but in 4lo the default is open diffs only, and that the yellow wire mod fools the computer into aiding traction even in 4lo.

My truck does not have a "vsc" button like the automatics I test drove, nor does it have any other traction related controls other than the 2h/4h/4l selector knob on the dash, and a trac off button in the overhead console.
Truly base model as far as these options go.

I put my truck in 4lo, and climbed one of my favorite steep rocky sections near my house that is fun and challenging in my 97 wrangler on 33's with lockers front and rear, and the Taco went up it no problem on stock street tires, with obvious computer controlled brake modulation in 4lo.
I'm aware that it isn't truly "A-Trac", but I didn't touch the trac off button, just shifted into 4lo, and walked right up a section that was almost impossible in my stock 92 4runner sr5 on 32" BFG KO2's with no lockers.
So for now, I'm of the opinion that there is some level of brake modulated traction assistance there, and that the yellow wire mod may be unnecessary on the 2017 base model 4x4 at least.
I am more satisfied with the purchase of this truck every day.

 

It has a description in your manual. You can change a few things with the trac button.