How does a trac work

The TRD trim is basically the SR5 package and Toyota adds off-road focused features to the existing platform such as:. It transfers torque to wheels that have the most grip on the ground by actively braking each wheel that does not have any traction with the ground. It optimizes power sent to wheels so the driver can have the most control over the SUV. It is ideal when in snow or mud-type conditions. It is an active process that acts in the same way a locking diff does.

It should not come as a surprise either. It is a simple system that has been in 4Runners for ages. It adds an immense amount of control to the vehicle, almost as much so as going from 2WD to 4WD. The Toyota 4Runner has been an offroading staple since the early s. It is almost as common as a Jeep in the hills. With this type of history, the amount of attention and experience off-roading would be hard to beat.

Toyota proves that with its features if offers in the 4Runner. The technology behind these features is not too complex, though few other automakers have it. If you wonder how does crawl control works it is not too different than locking differentials or all-wheel drive. ATRAC makes certain all four wheels are driving at a crawl speed by reducing engine output.

Crawl Control modulates the throttle to keep the vehicle moving at a crawl, but ATRAC does it automatically so your foot can stay on the brake pedal. The idea of Crawl Control is to maintain a crawl speed and it does that by modulating the throttle. This is where Crawl Control would modulate the throttle to keep the wheels turning and move your vehicle at a crawl. If you want an automatic 4WD system that can be used on hills, get one with Crawl Control. To understand the basics of this technology you should know that a differential is a gearbox filled with a special fluid.

It sends power to the wheels while allowing them to rotate at different speeds, thus avoiding wheel slip and keeping your vehicle going in a straight line. GreenheadKiller likes this. Great write up. Sometimes hearing about someone else's personal experiences really helps to understand these new systems.

The manual helps, but can almost make it more confusing. I am happy to put stuff down in a way we can understand As for when you use those 9 modes Seriously, the standard setting in H2 and H4 will work. I was amazed on how it took me over deep beach and arroyo sand without deflating the tires as always necessary before. Amazing technology makes our Tacomas tractors almost! Better to have it and not need it, then to need it and not have it! Try a steep climb and if you are halted before you get to the top There is more 'testing' to do, however!

We have the option of making the differntial s open in all three drives H2, H4, L So, you have traction opens galore! However, the standard mode in H2 and H4 will take care of you Have Fun Everyone!

David K , Feb 10, I am curious if anyone else has experience the following. I recently drove it in the snow and was curious to see how the traction systems operated. I have owned 6 previous vehicles with traction and stability control and have been an advocate for them and would not purchase a vehicle without them.

I have driven these previous vehicles extensively in snow-filled winters during my years in North Dakota My problem is that my new Tacoma doesn't seem to have a functioning TRAC traction control system in 2wd mode. I push no buttons, so this is in normal mode. There is most definitely NO throttle intervention when the rear wheels spin. If the road is flat, I can do this forever. The only time throttle intervention occurs is when the vehicle starts to slide sideways and I presume then the VSC is kicking in.

If you spin the rear tires wildly, the crown of the road will eventually get you sliding a bit sideways at the rear and then and only then does throttle get restricted. I did this just to test the systems and was very disappointed about the lack of traction control VSC or stability control worked well like in all my previous vehicles to keep the vehicle from fish-tailing or plowing.

I run snow tires studless Michelin Alpins and with careful use of the throttle I got around fine, but I'm just not used to NO throttle intervention when the tires spin. This goes against what is in my owners manual and what is posted above. I tried the same in 4HI and had the same response though of course it's a bigger challenge to get wild wheelspin in 4 hi--but I see that the tech info above says I should not see throttle intervention in 4 hi, but I should in 2wd.

Am I missing something? Can anyone else with a 6 sp TRD get the rears to spin out of control with no apparent intervention when in normal 2wd mode? Thanks for any responses!

In other words try all three 2WD modes and see if there is differences. My personal answer is use 4WD H No sense in thrashing your truck in 2WD, when you have 4WD.

David K , Feb 12, BrianTaco likes this. Wondering if Darenjpdx ever got it fixed or figured out? David K , Feb 18, We may never know? David K , Feb 20, After going up, around, and back down from there The rear locker may never be needed!? Just the long rutted out grade alone was a good test A rear 4X4 mud flap got pinched off This is where VSC plays an important role. VSC stability control functions to alter momentum to prevent oversteer or understeer. BB code is On.

Smilies are On. Forum Rules. All times are GMT The time now is AM. All company, product, or service names references in this web site are used for identification purposes only and may be trademarks of their respective owners. Toyota - 4Runner. Join us now! Mark Forums Read. User Tag List. Page 1 of 8. Last ». Thread Tools. Rate Thread. Thai Elite Member. View Public Profile. Quote: How much of torque can be transferred to the wheel with traction??

Find More Posts by dcampen. Bluto Senior Member. Find More Posts by Bluto. Quote: Originally posted by Thai Bluto, what car do you have now?? Hoomiester Member. Thai Good explanation and I now know how it works. Find More Posts by Hoomiester. Also an optional rear locker but not available with the stability system.

They just did not see the limitations. But Toyota's quality and my urban driving requirements make a 4Runner my only option. An 04 or 05 is another decision Less maintainance, better traciton up front.

Add some great tires, and it's all good. Re: Thai Quote: Originally posted by Hoomiester But if you sit around pondering stuff like this I fear you need to find a good significant other or hobby!

Quote: Originally posted by Thai Those Titan owners need to do more reading! BTW, in theory, when you lock the rear axle via locker , both wheels turn at the same speed Thus, traction control would not turn on because ABS sensors only detect differences in wheel speed and there is none with a locker.