3rd Gen Traction Control Modes Explained

I never saw an actual description of a test matrix or individual test results in any of the 2nd gen threads, but I probably missed several threads. (Note I don't mean conclusions, but the raw test procedure and results, maybe in some kind of tabular form that we can try and recreate.)
I tried very hard to do a comprehensive bench test on some of this stuff, and I agree that field testing is also needed. I would be happy to go run thru a test procedure and do a data record for 17 OR Auto, but I really don't want to write up the field test procedure because I think that takes much longer than the test itself.

So, if you don't mind too much, please put together a test procedure proposal, describing the models needing test, the test conditions (ground condition(s)) and test article setup (speeds, button presses, modes, lights), and any additional equipment needed. Include when data needs to be recorded, and in what form (pictures, videos, dash lights, log entries, speeds, OBDII data, techstream, etc). A properly laid out spreadsheet where we can record each test record for each test sequence is great idea too. Another question, are we going to purely trust dash lights, or do we need external verification of the wheel behavior for each test, or just some of them? If you put together a reasonable proposal that I can follow, I will do my absolute best to run thru it, remembering I am in Florida so no hills. That way we all can test exactly the same way and methods (within reason) to whatever method you think is the best. My first shot at getting multiple bench testing has not had a single successful retest (that I have seen, although at least 1 good attempt), so I don't plan on putting a bunch of effort on putting together a good proposal this time just to be the only tester.

I am not trying to be a dick, I am just saying you said you are "ubber fussy for the details", so if you think you have a comprehensive and specific test series and methods, write it up and I promise I will do my best to jump on doing it. Just make it as specific as possible.

(IE, Test 23. With vehicle on flat ground, 4Lo, No VSC button press, MTS On on Mid Setting, Crawl Control Off, Locking Diff Off -> Accelerate until Dash Indicates MTS deactivation. Record speed at deactivate. Decelerate and note if dash indicates MTS reactivated. Repeat 3 times to verify the same speed every time)

Make sense? What do you think?
[Edit for grammar because I suck...]

 

Anything would be great... and between all of us nerdy enough to perform these tests, we should have some good comparisons. In Florida, you don't have any hills, do you?
I found the easiest traction comparison is with a short/ very steep hill climb. Both a sand dune and a dirt hill... tires at street pressure (because to deflate would make it all too easy, lol).
In my 2010, I did runs at each level.. and not using momentum. Start at the base and just climb. Mark where forward movement was halted. I also tested in beach sand (the dry, deep sand above high tide) level ground and sloping beach.

The 2009-2011 4WD Off Road Tacomas had 9 traction modes. In 2012 (even late 2011), a TRAC OFF choice was added in H4, creating 10 modes (5b below). 3rd Gen has a discussion about TRAC or TRAC OFF being added to L4 (6a and 6b and/or 6c below)

Here are the levels of traction from least to most (more or less):

1) H2 VSC OFF (long button push)
2) H2 TRAC (standard mode, no button push))
3) H2 AUTO LSD (TRAC OFF, quick button push)

4) H4 VSC OFF (long button push)
5a) H4 TRAC (2009-2011 had no engine regulation, so = TRAC OFF, standard mode, no button push)
5b) H4 TRAC OFF (2012 + quick button push)

6a) L4 standard mode (2nd Gen=VSC OFF/ no button push) 3rd Gen??
6b) L4 quick push 3rd Gen??
6c) L4 long push 3rg Gen??

7) L4 A-TRAC/MTS
8) L4 Rear Locker (no A-TRAC or MTS)
9) L4 A-TRAC/MTS + Rear Locker

 

David K, thanks!

 

Hey guys, does atrac essentially enable auto-lsd qualities but in 4wd on the OR and pro? Because I know auto-lsd only works in 2wd, and many wish it worked in 4x4 that are sr5 or sport owners.

 

So I already described diffs sufficiently I would hope, right?

And Doggman posted a table at the beginning of this thread (that several of us together generated) that describes the traction control actions of all the 3rd gen trims for each mode.

Does this data not fully describe whatever you want to understand about traction control?

 

I saw a video where taco bandits friend tested his auto lsd with his sport. Then he went on to say he wished 4wd had auto lsd. So, I’m getting confused as to which is accurate since this thread says trac-off is the same as auto lsd in 4wd.

 

Switch 5a and 5b. The "2009-2011 no engine reg w/ TRAC" is still standard mode. H4 TRAC OFF turns off TRAC completely and thus does not yield increased traction.

Default 4Hi is comparable to ALSD in 4Hi. You get LSD functionality without regulating engine power. The only difference on the surface is VSC is still on unlike in ALSD. That being said the underlying code that runs TRAC and ALSD is likely different in some ways. ALSD is probably a bit more aggressive but perhaps not. Hard to say.

 

I yield to Doggman on his 2016+ research. He may be correct on the 2012+ H4/TRAC ON/OFF settings too.
I will await a time when I can personally test the modes as I had been relying on others or logic for 2012+ models.

 

A-TRAC is far beyond TRAC and AUTO LSD. It is more closely equivalent to front and rear locking differentials. It stops a tire from freely spinning and matches it to the rotation of the opposite tire on that axle so power is balanced... as a locker does.

 

A-Trac is a beast in our Trucks, awesome system!

 

Does anyone know if the published Gen2 VSC reset procedure works on Gen3. Slip light is on constantly after some beach driving.....

 

Well damn, thank you very much! I will give it a go in the morning and post back!

UPDATE: Worked perfectly on a 2017 4cly

 

Hope this is the right place for this question.

I just got my 2018 TRD OR. I went out to test the 4x4 system and ran into a situation where it seemed like it wasn't working. I went through a slightly off-camber creek. Was in 4-lo (confirmed with dash indicator - so in the "Default 4lo" from spreadsheet) with no MTS or Crawl Control activated. Both front tires were level and had weight fairly evenly distributed. The left rear tire was un-weighted (in a hole). Neither front tire would spin and the left rear spun freely. Crawl control would pull me out as well as engaging the rear locker. I did not try MTS only. This seems odd to me. It should be impossible for there to be no wheel spin on a driven axle - unless there is a differential in the transfer case?? If I get a chance this week I will go back and try the MTS only.

 

Are you sure the right front wasn't spinning? Like you said, the transfer is fully locking. Something had to be slipping up front if the rear left was spinning.

Could there be a problem with your front diff / ADD? Was the front driveshaft spinning?

 

I was by myself so could not get out. But did confirm there were no marks indicating the front had spun. I did go find some sand and could make the front spin and with MTS would spin holes for all four tires. I need to go back out with someone to video and see if I can replicate.

 

The only other thing that I can think of is that your weight in the drivers seat lifted the wheel when you were in the truck. Getting out let the wheel touch down?

Otherwise, I'm stumped.

 

That is an interesting observation. I would not have felt the front right spinning if it was in the air and it would not leave any marks on the ground. Rather than muck this tread up with more discussion - hold off and I will test this in the next couple days and report back.

 

MTS replaced the basic A-TRAC, by making it adjustable. I would NEVER use L4 without A-TRAC... it is just silly to let the tires spin instead of moving forward. The Rear Locker is NOT needed unless the other system fails (and I have yet to experience that) and is harder to use than MTS/A-TRAC which activate instantly and do not hamper steering.

I recommend always have MTS on in L4, what setting I guess depends on what terrain you are in... as I have just A-TRAC and the Rear Locker available in L4, besides the nearly useless option of open differentials only (when compared to traction control or lockers).

Your front and rear driveshafts are locked together at the transfer case. There is no third differential there as in an AWD car. If you steer sharply on dry ground in 4WD, there will be resistance as the front and rear driveshafts must rotate equally in 4WD and loose soil allows the tires to slip at different rates.

 

It is very unlikely that the add or transfer case not be locked when the computer thinks they are. Not impossible, but dang hard to trick it. The truck only checks the add and transfer on engine start and mode changes, so it's posssible to have it engaged and then come disengaged while driving. (But the only way i found to do that is apply a few flashlight batteries to the module, it won't come loose randomly).
If there is ever doubt about the engagement, you can either power cycle the truck while leaving it in 4wd (which forces a recheck of the add and transfer sensors), or mode change completely to 2wd, and back to 4wd.

If you do that and get no errrors, I will almost guarantee that you are in 4wd in both the add and transfer case (unless you did my 2 wheel low mod)