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

So do all 2013 V6 prerunner's have ATRAC?Basic and SR5 models?

 

A Prerunner is what Toyota calls some of their 2WD Tacomas. A-TRAC is a 4WD system on the 4WD Off Road Tacomas, since 2009.

 

... ^^^ ... LOL ... I like that vid of the ... "space guy" pushing all the buttons ... good one ... and true ...

 

I have an 03 Trd Dcab prerunner v6 with the rear locker button.I am considering upgrading to a 13, but would like to go w just a n Sr5 dcab v6 for the smoother ride.I do light offroading for hunting and do not want just an open rear axle.Will the sr5 not have a LSD rear,just one wheel spinning?

 

Ok so they do have an auto LSD.Just don't want to get stuck w a rear that only spins one tire..Thx

 

ALL Tacomas since 2009 have TRAC electronic/ brake created limited slip traction control, on an open differential. They all also have AUTO LSD, which is a select-able feature to increase the force to stop wheel spin (because of no engine output restriction).

It works, but still is not the same as having equal power to both tires as a rear locker provides.

On a wet day make a turn from a stop, first with just the standard TRAC, then again with the AUTO LSD on and compare. To see what it was like before any traction control, turn off the system altogether (stop moving, press and hold down the VSC button for 3-5 seconds, lights comes on)... and make the turn from a stop on a wet road... An uphill turn exaggerates the benefit of traction control more!

 

Cool, makes sense, thanks!

 

Glad I found this thread!

 

Here is a video I found that demonstrates ATRAC in action. The video is full of examples but pay paticular attention @ 1:15 here....

https://www.youtube.com/watch?v=PKl30rPjsG0&feature=youtube_gdata_player

 

I just returned from testing out my ATrac. I live near the MS river and the levee gets really steep in places. I found a sweet spot that's really friggen steep and made multiple attempts to climb it. 4H with out any button pushing was OK and would have got the job done if I were willing to get more of a running start, but that wouldn't have helped me understand the settings at all cause everybody knows that with enough skinny pedal you make it though most things.

Anyway, things got interesting when I went in 4L with ATrac ON and Diff Lock OFF, I started up this incline and made it about half way up then the wheels started to spin. Now to me it seemed like instinc to let off when the wheels spin but in all my reading about ATrac, I learned to just keep easing into the gas cause ATrac works best from 2000 to 3500 RPM. Well I did just that, I was on the side of that hill spinning my tires and I could hear and feel ATrac kicking in but I wasn't moving still. I stayed on the skinny pedal and watched my RPMs to try to keep em around 3Kish or so. Inside the truck the sounds coming from the systems were getting LOUD and didn't sound great but it still fealt like it was working. I stopped backed my way down again and engaged the Diff Lock. Once again I made it to the same spot (same little ruts I dug from last attempt) and started spinning but this time ATrac sounded MUCH more calm steady so to speak I guess cause it was only working on the front end, and I could feel it too. I stayed in the gas and when I got just over 3K RPMs it fealt like the ATrac came alive and the truck started moving forward. As soon as I noticed the movement I held the RPMs steady and ATrac pulled me right on up this hill. So after reading and learning about this system and actually seeing it in action I am amazed. I am SO glad I dropped the extra cash for the Off Road package.

 

I wish they would have offered TRD on a 2012 dbl cab long bed 4x4.....

 

this is exactly what it does for me. I haul large glass sheets over steep ledges
and skidder trails and I must creep. at creeping speeds I just start to
slip on wet stumps or mossy rocks. nice to have a locker and atrac is
a bonus so I almost never have to back up a foot and hit it again, just keep
on the gas and let the truck 'cripwalk' around and over the crud

 

Good job! There are many types of surfaces and Toyota has a traction mode of them! The only difference I noted when I just use A-TRAC and no rear locker, is when the truck seems to be not able to climb any further, I push down on the accelerator which seems to 'wake-up' the system... like it knows I am serious about getting to the top! So, there is a few moments when the truck doesn't move and by giving it the heavy pedal it begins to turn the tires again. This was shown in the video clip of me using A-TRAC at One Tri Hill in East San Diego County.

 

All true.

Not a bad system for "free" (the hardware is already on the trucks). Being locked rear and that up front from factory makes it really hard to justify an aftermarket front locker. The cost/benefit just ain't that grand.

Now if you drive an open/open SR5 off the lot...

 

As the saying goes, 4x4, lockers, armor, etc. all just get you stuck further from help...

 

On a truck equipped with the auto LSD, is there any advantage to installing a mechanical LSD? I will be doing a gear change soon, and figure as long as they are doing the work, might as well add a LSD at the same time.