ATRAC vs Rear Locker?

I dont have the owners manual with me at this time.

When would I want to use ATRAC and when would I want to use the Rear Locker? Is there ever a time I would need to use both?

 

Up to you. For the most traction use atrac and locker at the same time. Most of the time just one of either will get you up whatever your trying to do!

 

Why have both devices if they do the same thing?

 

They are different.

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

 

Correct me if I’m wrong, but on 3rd gens, once you lock the rear dif, A-TRAC/TRAC automatically turns off and you only have an open front dif.

 

Thank you for clearing this up. I was starting to wonder why my 17 trdor didn't have an a-trac button

 

3rd Gen TRDOR AT will not have A-TRAC because they have Crawl Control. 3rd Gen TRDOR MT do have A-TRAC because they do not have Crawl Control.

From the manual "When the rear differential is locked (vehicles with the rear differential lock system) The active traction control system is activated only when the vehicle speed is less than 3 mph (6 km/h)."

 

just for future reference also if you have the internet you have the owners manual,

https://www.toyota.com/owners/resou...al&gclid=CPmaxN3qrNgCFYhegQodQXcKOA&gclsrc=ds

 

Because sometimes you want to go places you really shouldn’t.





Also, they don’t do the same thing.

 

I browsed through the manual. Manual says atrac is for starting and acclerating in slippery conditions. Does atrac assist in slowing down or stopping in a snowy or icey spot? If not, what does?

 

Not true.
A-TRAC is active in Multi-Terrain and Crawl Control modes.

 

A-TRAC controls brakes and engine output...
Which model do you have and what position is the transfer case?

 

ATRAC and MTS are essentially the same thing with MTS allowing you to dial in the amount of slippage allowed before braking assist occurs.

As said, when the rear locked is engaged all braking assists are disabled.

Only use the rear locker when you’re stuck in the shittiest of shit and crawl or MTS/ATRAC won’t get you out...or if you’re a serious and experienced off roader who knows how to use it and the risks involved

 

2017 TRD OR (manual)

 

My statement was in reply to mytacoisweksos querie as to why his TRDOR did not have an A-TRAC button. I could have better stated this by saying that TRDOR MTs have an A-TRAC button and an A-TRAC light in the instrument cluster. TRDOR ATs do not.

 

Some have said ATRAC is different than the locker which is true but no one has said how.

The locker is pretty straight forward. When activated it locks the rear wheels together. All power sent to the rear diff is split 50/50 to each wheel no matter what.

ATRAC on the other hand is an electronically controlled traction aid that utilizes brakes to prevent excessive slip. This works on all 4 wheels. If a wheel starts excessively slipping it will apply the brakes to it so that power is sent to the other wheel which has better traction.

So in practice ATRAC accomplishes nearly the same thing as a locker but there's a significant difference.

As far as I know ATRAC is not designed to help in a slippery descent scenario. Toyota has DAC (downhill assist control) offered in other vehicles but it does not come on Tacomas. I would wager the DAC abilities are being used in the CC/MTS and further that DAC requires an automatic transmission.

I would like to think in the event of a slide it would do something to assist. It does have advanced systems on board to prevent locking up the brakes and skids resulting from extreme turns (TRAC and VSC) but it does turn TRAC off when you go into 4low. My guess is the ABS would still kick in but thats probably all you're gonna get. And truth be told that may be all you get in DAC or CC/MTS. I'm not sure there's more that can be done to prevent sliding than what ABS brings to the table already.

 

Yeah, I have been curious what, if anything, ATRAC does for downhill slippery stuff. I thought ABS is turned off when ATRAC is activated?

 

Pretty much...

As I understand it;
Crawl Control is DAC with selectable speeds using A-TRAC tech.

MTS is like a manual with A-TRAC engaged, but with selectable levels of slip/side-to-side power transfer; again, using A-TRAC tech.

TRAC(2WD) is engine control.
A-TRAC(4L) is engine and brake control.

 

I can't confirm or deny this atm but I think you're right. Can check if you're in the truck. If the ABS light comes on it's off. If that's the case probably worth turning ATRAC off if you want ABS.

 

I'm kinda sad I am reading this thread, and the linked thread...
https://www.tacomaworld.com/threads/a-trac-trac-auto-lsd-explained-easy-to-understand-i-hope.70551/
Realizing now that I have no idea how to truly best utilize the off road functionality (other than actually putting the truck into 4hi or 4low)... I did try out crawl control once when I couldn't move forward on an icy/snowy trail, but I never tried to lock the rear diff.
I thought auto - lsd meant that if I had one of my rear wheels slipping while in 4hi, it would automatically lock the diff.... I have no freaking idea.
I am going to figure this out.