Crawl Control... is it all it’s cracked up to be???

Still not sure i follow the logic of activating the locker(s) on the hw. Also, we can engage 4x4 with just the turn of a knob.

Unless you just do it for fun... lol

 

Also some OEM GX 460 optioned for crawl but all can optioned (modded) for about $300... add in MTS for another $200.. all models '10-Present.

I'd rather have more tools/features than what I need. I like options myself.

 

To answer your original question, I would rather have the sunglass holder. I prefer to drive my truck, not flip switches and push buttons so that it can move on its own.

 

Sunglasse holder cant hold sunglasses, most of my sets dont fit, so it's useless.

 

What happen when u stuck alone in the middle of no where and ur driving skills fails. No phone signal no one to help sun is going down coyetees howling and shit!
I don't choose to use it because I don' feel like driving I choose to use it whem 4low and locker all faile to get me out or when I feel like I even need to speed over rocks and break something or let it do it' thing safely

 

I am going to try and very specifically answer question about power and torque on locked vs ATrac/MTS vs Open. This will be long, follow along if you are interested. At the end there will be a test...

First a refresher back to high school physics.
Torque, has units of Distance×Force, like foot × lbf
Power, for rotational items, is Torque×Rotational Speed, like Ft×lb×Rpm... you would have to put a coefficient on there to get appropriate units such as HP, or Kwatts, but you should get the idea.

Ok, totally open diff first (without any traction control systems)
Torque is equal across an open diff, axle speeds aren't. This allows cornering without slipping. So an open diff torque to LH wheel is the same as RH wheel. For normal usage (wheels on ground) wheel speed is the same LH to RH and (torque is always the same LH to RH), so power LH = RH, for all practical purposes.

Now, take that open diff and get stuck with a wheel in the air and one wheel spins. Torque on both wheels are the same so the tire that is trying to do some work has the same minimal torque as the one in the air. Power is torque x rpm, so free wheel is consuming some power, and wheel on ground is literally using zero, because it isn't turning in the extreme case. 0% power to grounded wheel, 100% to floating wheel.

Now take that open diff and add MTS or Crawl, or ATrac. It's still an open diff, so torque is still equal LH and RH. But the computer adds braking to the free wheel and uses ABS sensors to match wheel speed LH to RH. So Tire Torque + Brake Torque are the same LH to RH. So lets assume that one wheel in the air again with the grounded wheel slowly turning. The grounded wheel has torque to the ground, the air wheel has brake torque added to give the same torque LH to RH. The computer adjusts to give same wheel speed LH to RH, so the grounded wheel is using the same power as the floating wheel. So with MTS/ATrac/CC, 50% of power to the grounded wheel, 50% to the floating wheel.

Finally lets talk of a fully locked axle. With diff locked, speed is the same LH to RH, but torque LH to RH is unknown (indeterminate in general). Driving with both wheels on the ground, we can't say for sure where power and torque are going. But if we put one wheel in the air, then the grounded wheel carries nearly 100% of the axle torque, and floating wheel almost 0% torque. Speed is same LH wheel to RH wheel. So for locked axle, ~100% power to ground wheel, ~0% to the floating wheel.

[BUT,
if we are talking stock OR/PRO, locking and MTS/ATrac only work in 4Lo. Are you really power limited in 4Lo that you have to worry about waste it on brakes (with Atrac/MTS). I would say these trucks are rarely power limited in 4Lo]

 

Yes, the off-road and pro have crawl, atrac, mts.

 

I've tried it on a hill decent. Was really impressed how it worked. But otherwise don't care for it . But love the multi terrain select. Works great in the rock setting

 

That's not quite right .

As you said, a differential allows just that, a difference between driver's and passenger's. Example is going around a turn, two different arcs scribed by the tires mean the tires travel at two different speeds. The diff allows just that.

And diff also allows power to take the path of least resistance .

So a wheel in the air is where all the power goes .

Locked means they spin at the same rate no matter what, so you can't actually have 100% of output to one side. It's always split when locked .

Applying brake on the side in the air in a electronic/brake type open in the air makes the path if least resistance the side with traction.

Both scenarios are running through the same gears in the diff, so there's no difference total output. If anything the brake on a free wheel allows all the output to go to one side of the axle while a locked diff will always split it 50:50.

There's no difference in total output between the two systems .

The advantage of a locker is it doesn't have to react. The two side will do their thing, regardless of the situation. It's also how you can break an axle when you have a spinning wheel in the air come down and suddenly gain traction .

The advantage of the brake systems is the power can be forced to go from one side to other. You also won't brake an axle from having a rotating wheel in the air suddenly finding traction, it's already been stopped by the brakes .

Disadvantage is that it uses the brakes, they can overheat, and it's reactive, so there will always be a delay.

 

No

Use the math, it makes it simple.
You only have to know two things. Torque on each side of an open diff is the same, speed is allowed to be different.
Speed on a locked diff is the same on each side, Torque is allowed to be different.
(Use Wikipedia or similar if you don't believe me https://en.m.wikipedia.org/wiki/Limited-slip_differential)

Use those facts, and you will come out with the correct answer...

Why people think a locked diff splits torque 50:50 I will never know... It just makes 0 sense.

 

There's a total output from the drivetrain of your vehicle. It's total sum of all the motor, transmission, differential, etc. The amount of mechanical advantage they impart, losses to friction, whatever .

There's a value that is the output at the tires on the ground.

Say torque, as you said.

Show me the math that allows for the total output of the system to change solely because the power is going to one side of an axle to another vs both sides spinning at the same rate.

Its a fixed system.

Let's say the truck puts down to the ground 220lb/ft of torque at the tires after parasitic loses.

In an open diff, that's the sum of the output on both sides. There can be more on one side or the other, but that'd be the total, 220lb/ft. Like you said, output can vary side to side to allow turning.

In a locked diff, the output is fixed so there can be no varience side to side. The amount of torque present would still 220 lb/ft, it's just split equally between the two axles. They're spinning at the the same rate. No speed difference, no torque difference .That's the whole premise of a locked axle.

Brake lock diff. Tire in the air. Some value of torque is allowing it to spin very slowly while the brakes hold it, the rest goes to the other side. Total sum, still 220 lb/ft . Everything can be different, still has the same total output .

Only torsen diffs have some kind of mechanical difference side to side, but those would never e used because they use a geared multiplier. A tire in the air has zero traction .The multiple of zero is zero, so it would act like an open diff.

If you read what we've written they're almost the same thing . The only thing I disagreed with you in is your statement that torque is allowed to be different in a locked diff. Speed and torque would be the same across the axle. That's why it's locked .

 

To an extent I think the best way to explain is break a CV in the front, no level of traction control will get the good CV to turn .But lock the front diff and low and behold you have front drive again as long as nothing was damaged in the diff .

And it still takes some slip before it locks a brake.
Nothing can replace the greatness of a locker

 

Excellent point .

When you're in a situation where a locker is actually needed, there's no substitute.

It's just up to that point the electronic systems can preform with such effectiveness that you can get by without one.

 

I haven't found a time where the rock setting hasn't helped. Most of where I go is Canadian shield rocky trails. I try to avoid mud. So can't really speak to how mts works on other stuff. But rock I've been blown away with how well it for compared to 2nd gens I wheel with that have nothing

 

Never used it until this last weekend. Still didnt need to use it, but someone convinced me to finally give it a try. After I fumbled around for 5 min trying to figure how it worked it moved me forward out of a real easy spot I was slipping on that just needed a tad more gas....that should be all I need it for unless I get stuck in snow somehow somewhere.

 

I haven't tried the MTS setting with mud yet either .

Instead, I tried crawl control going up a rutted, muddy slope following a Jeep like I said in my original post.

I was so impressed .Truly impressive stuff. I'm coming from a JK Rubicom Unlimited, 3.5" lift, 35s, etc. For anything other than traditional rock crawling, I find what the Tacoma with MTS and crawl control to be equal or better.

 

I have to words to everyone who thinks it's the most useless thing ever: Murphy's Law. As unlikely as it is, there's always a chance that x, y, and z will fail. If that happens, crawl control may be your only option. I'd be much happier to have it, and never have to use it, than not have it in a situation where I might actually need to use it. Plus it's good for people who might not be as experienced(And to those of you who say "Then you shouldn't be doing it!", did you learn to do it by sitting on your asses? No, you get out, and PRACTICE, doing it is the only way to get better), so to me, the idea of crawl control is great, another thing that could possibly help you out on the trail.

 

By far my biggest complaint. Pisses me off.

 

Just curious, why didn't you just stop and get pulled out? I think by the time it got to the point that I wouldn't recover, I would stop for that very reason. But, again, I might not have thought about it either. But I really do try to not do things that might hurt my truck. Not knocking you, just wondered what made you keep going. Did it seem like it would pull out?

 

1. Shouldnt wheel alone.
2. There's a thing called a winch that is far better at anything to getting you out. If you pull the no anchor argument, see point 1. Or use an anchor like I have purchased like a pull pal 9r deadman

See above.



Most of you have seen to forgot the biggest no no of wheeling, dont go alone. And nothing can replace the piece of mind a winch can