3rd Gen Traction Control Modes Explained

Ok. But the Manual says MTS can only be operated with Crawl Control OFF. I understand that when in Crawl Control it includes the wheel limiting slip of the brake induced traction control. So in a way Crawl Mode includes the MTS feature. However, MTS alone allows you to select the amount of slip allowed before the brake induced slip control operates. Using the knob there are 5 selectable values. That same knob is essentially the speed control (cruise control if you will) for crawl mode. You can’t actually turn on MTS and Crawl using the 2 push buttons. If I hit one of the buttons , say Crawl, while in MTS, the instrument panel message says that mode is not selectable, I’m almost sure. Have you ever been able to select both MTS and Crawl simulataneosly?

 

CC may operate with MTS functionality BUT it must assume some allowed (pre-programmed slip) associated with each speed on the 5 position knob. Again, when in MTS mode the 5 selections proceed from position 1 Mud (allowing much slip before intervening with brakes) To position 5 rocks not permitting much slip before intervening with brakes. When in Crawl mode the selections are just speed with 1 being slowest and 5 being fastest. You can’t select a slip limit (1-5) while in Crawl, only the speed at which you crawl. I’m guessing the permitted slip in Crawl is very low , perhaps the least slip associated with Rock setting (5)? I’m not sure. Seems to me when in crawl there would be very little sip desired.

 

I wish they made it this clear in the manual, thanks guys!

 

If we want to get technical then technically MTS is an adjustable slip version of A-TRAC and CC includes A-TRAC functionality embedded. A-TRAC is the base system created by Toyota that all these 4LO traction control systems are specific tunes of.

 

ShimStack, I studied this system in February 2016 when I got my TRDOR. My notes say “MTS is adjustable slip version of ATRAC”. I came to the conclusion comparing the Gen 3 Auto Trans version to the Gen 2 with ATRAC. What I am not sure about is how much slip Crawl Mode permits before using brakes to limit wheel spin. As I explained above it is most likely the slip permitted in the Rock setting of MTS (least amount of slip). It has to work on rocks and in mud it would still work. What do you think?

 

Try reading this post
https://www.tacomaworld.com/threads...l-modes-explained.530695/page-7#post-17023370

I attempted to test MTS vs CC (with techstream). Read the post for more detail...

 

That I don't know. But if I was forced to guess I'd say CC slip ratio adjusts a little based on speed selection and correlates with the chart in the manual. Notice the CC speed chart correlates to a terrain and those terrains correlate to the MTS settings. This is my guess.

If I was curious and owned an auto I'd check the traction control states via Techstream while operating CC and see if they show any adjustment with CC speed. If that didn't shed light I'd log wheel speeds and brake activity to figure out what slip ratios cause braking intervention and if that changes with the CC set speed.

 

As you say, need to do full logs to learn more.


I didn't research enough of the techstream data to know if there really is a difference.
However the computer knows (and remembers) if you have MTS on when you turn on CC.

(Deleted double post - whoops)

 

I would say the Owners Manual implies the Crawl permitted slip is in the reverse order of the MTS selections: In Crawl-Rock it permits low slip which would be the highest MTS setting, In Crawl-Mud/Sand it allows more slip as in the lowest MTS setting. My original comment was referring to the MTS + Crawl reference. After our discussion here, it seems even though you can’t select the MTS button while Crawl selected OR Crawl button while MTS selected, the two are intertwined. When in MTS mode the truck speed is controlled by the transmission selection (D,4,3,2,1) and gas pedal while when in Crawl Mode the truck speed is controlled by the 5 position knob. It appears Crawl has pre-selected permitted slip values in line with conditions described by the MTS/Crawl selection knob.

 

Let's log!!

 

At last job, we used an (ironic) MTS test system (https://test.mts.com/en/products/test-system-components/flextest-controllers) for static and fatigue testing and data logging.

With the cards we had installed in it, dang thing could do over 1000 channels at 1024 hz (max).

Thing made data tables that would destroy any mere mortal PC...

 

You guys look pretty serious with interface capability with truck computer. I would interested in what you find out.

 

Good 'ol MTS! Pretty familiar with some of their bigger motorsports stuff. There's so much capability and capacity available across the board now it's great. MTS, NI, McLaren, MoTeC, and the still hanging around Cosworth Pi. And that's just the stuff I've dealt with.

 

I have read through this thread and it is still confusing. I am a new '21 TRD OR 4x4 owner, and want to know what these should be set at for the most fuel-effieicient "normal" 2WD driving? Thanks in advance!

 

Neither of those modes work in 2wd, so none

 

Traction control isn't causing any adjustments during "normal" driving. If you aren't applying enough throttle to break traction, cornering hard enough to begin skidding, or evasive maneuvering it's irrelevant what mode you're in. If you get in those situations often enough to worry about their effects on fuel economy you probably should have a YouTube channel.

 

My precious!! Oh wait..................

 

Thanks for your help ma'am, I'll keep that in mind next time.

 

Such a great thread, thanks all for contributing the info, and for OP for distilling it into the awesomely clear first post.

I feel like I've got a pretty good grasp of TRAC, MTS, and Crawl... my question is now, when would the rear locker actually help beyond what MTS/Crawl can do? Like in what kind of hypothetical situation might I go, "huh, Crawl just ain't gonna do it, better lock out the year diff."

 

https://www.tacomaworld.com/threads/stuck-1-wheel-spins-2007-auto-lsd.694466/#post-24556590

The simple explanation is a brake actuated traction system cannot max out the use of ALL available grip. A locker does, always.