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

You began your list with TRAC OFF lit... so, did you press the button just after turning the dial to H4 instead of noting the standard mode first?

Yes, I agree they very well could have totally switched it up on 2016! Or, maybe your truck has an issue, because others have not reported a lack of enhanced traction after pushing the button... or as you state, less traction than the standard TRAC mode (no pushing button first).

 

Well, maybe it is totally changed, as that is two of you. So, there is no traction difference between TRAC OFF and VSC OFF... you have two tires spinning either way?!! What is the point of TRAC OFF and VSC OFF, do you guys think? That is really sucky to lose a higher traction level in 4WD! I guess I will never trade in my second gen!??

 

Shoot. Several posts ago, I recall saying I couldn’t believe I was fired up about brake actuation and not a locker. Still feel this way and don’t feel ANY regret about trading in the ‘12 OR that had a locker and atrac. Chief86 squashed it by pulling out that stuck Chevy with a stout L4...no locker.

 

Hey to anyone concerned about the LSD vs locker. I don't think you're gonna be able to tell it. I was disappointed to hear it wasn't a genuine traction differential after buying my truck expecting one tire pulling and switching back and forth but if it switches the scratch sure as hell doesn't give that away.
I've had a truck with a real locker in it and that sucked donkey balls as a daily driver. I removed it after a couple years of chattering wheel hopping and driveline binding driving. I also drove a Camaro with a 10 bolt limited slip traction diff which was quite a bit better with friction modifier in it. I think Toyota nailed it with this setup. Oh I havent felt any engine cutout when spinning tires but I do know what that feels like. I had my wife's car do it a couple times in the rain on curvy roads. Feels like the engine dies, you stab the pedal again and it's like a dead pedal. Then gains traction and picks back up.

 

Nuff said! Now it’s time for the rest of us to play and get seasoned.

 

Get sum!

 

The engine cutting power is quite noticeable as I pulled into some deep snow the other day in 2 wheel drive and as soon as the back tires started spinning the entire truck started shaking and bucking like a dog shitting razor blades, quick press of the button and I drove right out.

 

This is sad. @David K knows more about these traction control systems than anyone in here and yet you tell him off.

Either way from what I'm reading it makes sense.

Toyotas definition of VSC and TRAC

• VSC (Vehicle Stability) Helps the driver to control skidding when swerving suddenly or turning on slippery road surfaces
• TRAC (Traction Control) Helps to maintain drive power and prevent the drive wheels from spinning when starting the vehicle or accelerating on slippery roads

Those are two very different things. VSC isn't going to kick in during burnouts or lifting tires while crawling. VSC is for when you swerve to avoid a moose going 60mph. TRAC on the other hand is designed to maintain effective power transmission to the ground. Prevent excessive slip. And TRAC will cut engine power. So given that both of your results are to be expected. With all systems on it does its job. With TRAC OFF you no longer get TRAC and thus no engine regulation and you can do your burnouts and what not. I do think in this mode if you did some really crazy shit you would see VSC kick in.

Also, you do not get ALSD in 4HI. Toyota has always said that is a 2wd only feature. So to expect it to do ALSD things in 4HI TRAC OFF mode is just wrong.

 

The one thing that I never liked about atrac is that it would turn off once the 3mph limit was reached. I honestly couldn't tell the difference, other than control, at going up steep hills at Hungry Valley when compared to the OR's locker.

The '12 OR did very well in pulling people out of jams going up and down this crazy mountain. But I have a strong feeling this SR5 4x4 won't have a problem whatsoever. The recoveries will be even more controlled. Control beyond 3mph.

 

On a side note. Anyone else finding, that while in 2wd and alsd engaged, the systems turn back on at 33/34mph and not 30mph?

 

I think David K has provided alot of great info, especially on the previous generations. However, I disagree with the above based on my 2017 TRD off-road automatic in 4Hi, with a quick press of "VSC off" switch.
That combination mode illuminates the "TRAC-OFF" light on my truck, and with two wheels jacked up I cannot get ANY brake operated LSD operation. Those wheels just spin away wildly. I can't seem to get any traction control in THAT mode on my truck.

 

The light on my dash goes off at the same 33/34mph.

 

ATRAC only turns off past 3mph if the rear is locked. Also when the rear is locked ATRAC no longer serves any purpose in the rear. If you unlock the rear you can use ATRAC up to any speed.

My guess as to why ATRAC gets disabled past 3mph with the rear locked is that its a safeguard for the rear end. Strong brakes to individual wheels do not mix well with a locked differential. That being said I wouldnt think ATRAC would trigger because the wheels are in fact locked to the same speed but if for whatever reason it did and you were going fast it might literally destroy itself.

 

Thanks for the explanation of what could possibly go wrong. I hear Toyota’s reasoning on that one. I just never liked it.

Toyota has to do a much better job of explaining things in their manuals. We all know TOYOTA looks at sites on how to improve based on what users are saying. The yellow wire mod must have led to not having to do it on the 3rd gens. The new bed d rings on the side are a case in point also. They were added very close to where I remember adding d rings under the bed bolts up front. So that was nice to see.

World goes generalizing and it’s the blind leading the blind. Although, some of you in this thread have led the way!

 

Same as 2nd Gen 2WD Auto LSD, in that VSC is off to 30 mph then come on. TRACtion control is on, all the time, without engine regulation (and here called TRAC OFF MODE and AUTO LSD by Toyota).

 

You would have have to jack up just one tire per axle, not both to have the rotation sensors detect an uneven rotation due to loss of traction. Do you want to drive it off the jack? In the real world, just put one side of the truck on ice or mud while the other is on dry ground. TRAC OFF will give more power to move you, as brakes halt the tires without traction. With regular TRAC, there will be throttle cut (engine output regulation) as well as braking to halt tire spin.

 

It is late, but I think this was answered... if not: A-TRAC only goes off at 3 mph when the rear is locked. You don't need a locker with A-TRAC... not really.
When A-TRAC is "on", it is just on standby should any one tire lose traction (spin). A-TRAC is far stronger than TRAC or TRAC OFF at matching tire rotation across an axle... almost like locking the two together... but only as long a needed. This allows easier steering, unlike lockers. Think of A-TRAC as an "automatic" or "smart" locker. Yes, there is hesitation and more spin between activations, but it does work and comes on the Off Road TRD at no additional cost.

 

That's because with both rear wheels up in the air...the truck doesn't think it's slipping...since both tires are spinning freely at the same speed.why would it think to regulate anything?

 

Only picture I have of the ‘12 OR, lol. Oh I know what a I had, but John’s description made sense as to why it shuts off with the locker on. I just never liked it. I believe what YOU should do is get into a 3rd Gen non OR and feel the magic quite a few of us are experiencing with the alsd on all fours. I think you will be totally surprised like I was.

 

x2.


I do 1200' in 2.5 mile of winding trail, part of which is a trail width of mountain runoff water. A-TRAC W/O the diff locked lets me keep that momentum through the wet stone and into the silt. Also gets me out of the silt.

Only time I've used the locker was put a tire on someones front lawn when there was a 1/4 of ice on a steep road and used it to push me to the top.

Aside from that, full faith in A-trac. Sorry for the hi-jack. Just thought I'd share my experience.