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

What is a "TSB"?

Thanks.

 

Technical Service Bulletin

 

Yah, I see it in your link... I guess this is what Isthatahemi was so upset about and traded the truck in for an Off Road 4WD. It is also a bummer that you guys can't get the Off Road TRD in a double cab! Is it much of a problem to cross to this side and buy the truck here (then take it home to Canada)?

 

Incorrect.

It was an option for 2005-2008 4wd TRD Offroads.

If equipped with the optional package, the 05-08 and 09+ share the same system with two exceptions: 09+ ATRAC works with the locker up to 3mph; 09+ has an ATRAC button.

05-08 ATRAC is traction control in 4WD. Low and High.


Taken from a 2006 Tacoma Factory Service Manual:



More on the 2005-2008's here: http://www.tacomaworld.com/forum/te...hac-dac-alsd-atrac-explained.html#post4388605

 

OK , my bad .

First I have heard that ATRAC was an option on earlier models .

I was pointing out that only TRD Offroads have ATRAC , not all Canadian Tacomas ( Base , SR5 , Sport ) as suggested by an earlier poster

 

Just to be clear... TRAC (and A-TRAC on some?) was an option, if offered at all on the 2005 (or '05-08) models.

I had an '05 TRD 4WD Off Road (which I thought had everything on it)... but did not have ANY traction controls beyond the standard TRD OFF ROAD's rear locker and otherwise open diffs.

 

I don't know about the 05's and 06's but VSC,TRAC,HAC,DAC came as optional equipment on my 07. Reading through the owners manual the traction control system (TRAC) sure sounds like ATRAC if you ask me...just saying.

 

In light of GP3's posts about ATRAC being available prior to the 09+ Offroads , I would like to revisit your suggestion that ATRAC is in fact included in the Canadian trucks , without the button , as is the set up included in GP3's findings for pre 09 trucks .


http://www.tacomaworld.com/forum/te...ds-vsc-trac-hac-dac-alsd-atrac-explained.html

Have you ever tried to kick the system in ?

 

I'm going to respond over in the 2005-2008 thread so I don't clutter your thread with 05-08 posts.

 

David K thanks for all the great info on all the traction options for the 09+ TRD Off Road Tacoma's! I got a 2012 TRD Off Road a month ago and was wondering what exactly Active Traction (A-TRAC) was. You explained it all in very good detail. Plus I didn't even know that we had the option to turn off LSD and have open differentials, that's awesome! I figured with TRAC that it wouldn't be a possiblity. TW is very helpful!

P.S. Have you ever used DAC?

 

Thanks for the kind words and I am glad it helped... I was so excited about the advanced system over my previous two 4WD Tacomas, and I didn't see a very clear write up about how and when to use the drive modes (that I understood well)! If I do a new thread on the traction choices, I will condense it and make it as easy as possible... this thread got real wordy and some distractions.

DAC:

Yes a few times... it does work, but it takes some bravery to remove your foot from the brake pedal when you go down a super steep grade (let's say 'cliff')! Works only in Low Range... and unlike just letting the Low Low transmission slow the downhill speed, DAC actually uses the wheel spin sensors to prevent any sliding to insure you go downhill straight.

 

I wonder why cometimes when you need to go to L4, and then lock the differential, it will not go into it?? I put it in neutral, wait, it just blinks?

This is my main issue, if I ever really need to use this mode to get unstuck, what do I do if it wont engage? Am I doing something wrong, but when I test this, it does not go into L4 and then Locker most of the time.

 

Today I went into L4 and locked the rear (I was going to pull a fork lift out of the mud if another one couldn't... it did)... Going into L4 took two tries (no biggie) but as soon as I pushed the rear locker switch it engaged without moving... and it usually does for me on my 2010. My 2005 often took more than one repeats of the steps.

Because this is an A-TRAC info thread, and I see you have a 2011 Off Road... if it is a 4WD, then you do have A-TRAC and using the rear locker is probably mostly unnecessary. Just push the A-TRAC button when you are in L4, and you will have locker-like traction on the back AND front! Use of the rear locker with A-TRAC can be saved for the most extreme or emergency situations, or like me to 'test them out'!

Have Fun!

 

We dont have mush snow this year, BUT, I was just testing to see if I get stuck deep in snow and don't want to get out to shovel, my course of action is if I start digging deeper in H4, then my plan of action is L4 with A-Track and then Lock the diffentials as the last resort.

But when I tried this when I was starting to get stuck on a sandy hill, it would not go into L4?? Of course I just backed out and built up momentum to get me out, but I just wanted to see if I could crawl out of it slowly in L4 with Locked Differentials. Since then I lost my confidence if I can engange the Locker if stuck.

 

Seriously it is that easy... Don't wait until you need it to try it the first time!!! In front of your house, on a straight road/ street (no turning needed), go into/ out of L4 multiple times... STOP, put in N (not Park), turn dial to L4 (depress while turning). If it beeps, do it over. Drive a short distance to feel the low range power (also press the A-TRAC button once in L4, and it will always be active in L4... until you press it again, that is).

Once you have mastered L4, then (in L4) press the RR Locker button. It may come on right way, or it may come on after rolling a few feet. Whenever you push the button the indicator light will flash (even in 2WD)... But, the rear is not locked until the light is on solid (not flashing)... and that is only in L4 (unless your do a locker anytime mod.).

Once you are comfortable that it will work for you, then go off road with it.

As I have said, with A-TRAC you may never need the locker... but good to have it as a backup!

 

GeoTaco1, Your concern is not lost on me. My 2012 seems a little finnicky getting into RRLock. Here are my thoughts:

For any transistion from one mode to another the transmission, transfer case, and differentials must have their various gears aligning properly. Thus the flashing icons until the system sensors sees everthing is lined up.

When going from H4 to L4 AND the system is under load (like your sand trap example) the gears can be "mis-aligned" and if you're in a bad spot you may not be comfortable letting the truck slip back/forth.

But that is exactly what I have found I have to do. As DavidK states; 1st get into L4 using the Neutral Tranny setting. If you do this with ATRAC off it is actually easier since the Diffs open up and things can line up easier.

Then click on the ATRAC to get out of your mess. If you still need the RRLock go ahead and turn it on while in Drive. You may need to rock back/forth a little bit to get it to stop beeping and engage.

When I am in a steep place and I go through this little exercise I hear/feel a "clunck" from the rear end and the all the flashing lights stop. That sound bugs me but I figure I would rather have the noise and get into L4/RRLock then not.

So give it a try and tell me if it makes your transistion any more reliable. Having the stuff work on flat paved roads is nice, but having it work in an axel deep bog-down is where it really counts.