Trying to understand center diff. vs. rear vs. front lock (3 Viewers)

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As far as I know (and I don't know a lot), LX 570 have the center diff. lock which I believes that means split power between rear and front wheels 50/50 only. This does not mean rear and the front wheels are locked, correct? I still have limited-slip lock in the rear and front, right?
 
The 200 is an all-wheel-drive vehicle and AWD is what you have with center diff unlocked (normal, most of the time). Locking the center diff essentially turns your AWD vehicle to a 4WD vehicle. With the center diff locked the output shafts from the transfer case (front and rear) are locked and will spin the same which sends the power 50/50 front and rear. So hitting the center diff lock in an AWD vehicle is the same as shifting to 4hi in a part time 4WD pickup (like my Tacoma). In either case, though the front and rear differentials are still open meaning they allow different rotational, speed left and right. The next step is adding front and rear differential lockers. I this is the only way to get all four wheels to rotate the same regardless of traction.

Generally speaking the 200’s all wheel drive system with traction control and MTS is pretty awesome. It handles most situations. I tend to only use the center diff lock on steep inclines (off-road of course) and I often shut it off going downhill off-road. Especially if there’s hairpin turns or situations where I feel the need I need to maneuver in tight spots.

Here’s an an article that explains the basics.

 
As far as I know (and I don't know a lot), LX 570 have the center diff. lock which I believes that means split power between rear and front wheels 50/50 only. This does not mean rear and the front wheels are locked, correct? I still have limited-slip lock in the rear and front, right?
Yep. The simplest way to put it is that the center diff sends equal power to the front and rear differentials. Stock 200 series have open differentials front and rear.

Worst case with CDL unlocked, you could have drive power to one wheel. Worst case with a locked CDL is power to two wheels, one per axle.

Unfortunately, with open diffs, the wheel with the least traction gets power.

Put some aftermarket lockers and you can lock as many or few wheels in as you want. Front lockers lock both wheels on the front axle together. Rear lockers lock both of the wheels on the rear axle together. Front, center and rear diff locked locks all four wheels in.
 
Thank you for the explanations. Just curious, are after market lockers electronic or do I have to manually go in a lock it?
 
For us, usually either air activated (ARB style) or electronic (Eaton/Harrop). There are cable lockers too (like the Ox locker), but I haven't seen them for the 200.

We don't have a manual locking hub option on the 200.
 
Also note that while it’s good to understand how this stuff works and maybe use that info to plan for a build, if you don’t know what the different lockers do you probably shouldn’t be going places that front and rear diff lockers are required to get to. The rear locker on TRD off-road first gen tacomas got some of those owners into situations they shouldn’t have been in.

Even without axle lockers the 200 has the ability to selectively apply brakes to wheels without traction thereby sending power to the wheels that do have it. Like having a pseudo-locker.. not a complete replacement, but it’ll do a large percentage of what one would do.

A stock cruiser will do very impressive things, and lockers only add to that.
 
Also note that while it’s good to understand how this stuff works and maybe use that info to plan for a build, if you don’t know what the different lockers do you probably shouldn’t be going places that front and rear diff lockers are required to get to. The rear locker on TRD off-road first gen tacomas got some of those owners into situations they shouldn’t have been in.

Even without axle lockers the 200 has the ability to selectively apply brakes to wheels without traction thereby sending power to the wheels that do have it. Like having a pseudo-locker.. not a complete replacement, but it’ll do a large percentage of what one would do.

A stock cruiser will do very impressive things, and lockers only add to that.
Thank you for the additional tip, much appreciated! No, I'm not looking into putting lockers in but very curious as to what it all involves.
 
Also note that while it’s good to understand how this stuff works and maybe use that info to plan for a build, if you don’t know what the different lockers do you probably shouldn’t be going places that front and rear diff lockers are required to get to. The rear locker on TRD off-road first gen tacomas got some of those owners into situations they shouldn’t have been in.

Even without axle lockers the 200 has the ability to selectively apply brakes to wheels without traction thereby sending power to the wheels that do have it. Like having a pseudo-locker.. not a complete replacement, but it’ll do a large percentage of what one would do.

A stock cruiser will do very impressive things, and lockers only add to that.

I guess i never thought about this, but do you guys with additional lockers not use MTS and crawl when you activate them?

You wouldn’t want it to brake any wheels, but then again locked, they will all “slip” equally in theory.

I will eventually use this stuff… i swear
 
I guess i never thought about this, but do you guys with additional lockers not use MTS and crawl when you activate them?

You wouldn’t want it to brake any wheels, but then again locked, they will all “slip” equally in theory.

I will eventually use this stuff… i swear
We can only really adjust the degree/type of MTS in low range, not turn it off completely, that I'm aware of anyway. Crawl however, we don't need to turn on.

Either way I don't see any need to disable MTS, since a locked axle shouldn't ever allow one wheel to spin at a greater speed than the others for the vehicle to sense that and apply brakes. A tire two feet in the air would just spin at the same speed as the one on the ground so the traction control wouldn't have any way of knowing it didn't have traction.

Crawl could still be useful for the automatic throttle and brake modulation to maintain the set speed, though I'd assume most people with lockers are competent enough to consider that off-road cruise control more of a hindrance than a benefit.

It's a bit different context than for lockers but I'm curious what was done with the Baja 200 and 300 to reduce VSC/TC intervention.. @cruiseroutfit any word on that? I would probably need to be ECU-level coding/modification right?
 
Thank you for the additional tip, much appreciated! No, I'm not looking into putting lockers in but very curious as to what it all involves.
This is a great video to explain the various lockers.

To replace them, you need to remove the differential housings. This involves draining gear oil, disconnecting the axles, removing the clamshell (front) or housing (rear), removing the differential assembly, replacing the open diff with your locker and ring/pinion gear, replacing bearings, reshimming/fitting (way beyond my skill level), then reinstalling everything, refilling, and bob's your uncle.
 
I guess i never thought about this, but do you guys with additional lockers not use MTS and crawl when you activate them?

You wouldn’t want it to brake any wheels, but then again locked, they will all “slip” equally in theory.

I will eventually use this stuff… i swear
I've used all the tools: MTS, Crawl, turn assist, center, front and rear diffs. They all have their place.

One example was two weekends ago, wheeling offroad in snow/ice on a steep off camber downhill. Crawl control worked pretty well for this. Could I have done it without, yup, but since I had it, I figured I'd use it. It helped reduce the pucker factor.

But I think I misread your question. I haven't mixed and matched crawl control and lockers. I usually turn crawl control off unless I explicitly want it. I haven't noticed MTS activating when I was locked (not saying it can't happen, I just haven't seen that).

Also, I don't often lock my front axle, but lock my rear more frequently. In this situation, I'd think there is the possibility to have wheels turning at different speeds and trigger MTS.

Side note: I turn off VSC and RSCA any time I'm offroad.
 
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We can only really adjust the degree/type of MTS in low range, not turn it off completely, that I'm aware of anyway. Crawl however, we don't need to turn on.

Either way I don't see any need to disable MTS, since a locked axle shouldn't ever allow one wheel to spin at a greater speed than the others for the vehicle to sense that and apply brakes. A tire two feet in the air would just spin at the same speed as the one on the ground so the traction control wouldn't have any way of knowing it didn't have traction.

Crawl could still be useful for the automatic throttle and brake modulation to maintain the set speed, though I'd assume most people with lockers are competent enough to consider that off-road cruise control more of a hindrance than a benefit.

It's a bit different context than for lockers but I'm curious what was done with the Baja 200 and 300 to reduce VSC/TC intervention.. @cruiseroutfit any word on that? I would probably need to be ECU-level coding/modification right?

The Canguro 200 (LX570) has all VSC, CC, etc fully removed. We run 100% manual (non-boosted) brakes with manual bias'ing.
The Jaos LX600 still has all of those items functional at current.
 
The Canguro 200 (LX570) has all VSC, CC, etc fully removed. We run 100% manual (non-boosted) brakes with manual bias'ing.
The Jaos LX600 still has all of those items functional at current.
Did that require any trickery with the ECU/TCU to prevent power cut?

Tape over the MIL?
 
I've used all the tools: MTS, Crawl, turn assist, center, front and rear diffs. They all have their place.

One example was two weekends ago, wheeling offroad in snow/ice on a steep off camber downhill. Crawl control worked pretty well for this. Could I have done it without, yup, but since I had it, I figured I'd use it. It helped reduce the pucker factor.

But I think I misread your question. I haven't mixed and matched crawl control and lockers. I usually turn crawl control off unless I explicitly want it. I haven't noticed MTS activating when I was locked (not saying it can't happen, I just haven't seen that).

Also, I don't often lock my front axle, but lock my rear more frequently. In this situation, I'd think there is the possibility to have wheels turning at different speeds and trigger MTS.

Side note: I turn off VSC and RSCA any time I'm offroad.

That second part is exactly what i was wondering about!

Thanks!
 
The Canguro 200 (LX570) has all VSC, CC, etc fully removed. We run 100% manual (non-boosted) brakes with manual bias'ing.
The Jaos LX600 still has all of those items functional at current.

In regards to the brake bias adjustment, ive been wondering what kind of results adding some more rear bias would provide on an otherwise stock weight rig with oem rake. Would that also work with the booster normally?

Ive seen an adjuster somewhere in the million pages of FSM.

I feel like the fronts wear faster than rears in stock form. I might want to dial it to the back just a touch.
 
In regards to the brake bias adjustment, ive been wondering what kind of results adding some more rear bias would provide on an otherwise stock weight rig with oem rake. Would that also work with the booster normally?

Ive seen an adjuster somewhere in the million pages of FSM.

I feel like the fronts wear faster than rears in stock form. I might want to dial it to the back just a touch.

Or i really really should stop messing with things…
 
I agree that every traction control strategy has its place. Physical lockers heightens and adds abilities. There's some things that pseudo lockers can do that physical lockers cannot, and vice versa.

One interesting observation with CRAWL is its ability to take advantage of static friction. If you remember back to your physics classes and the difference between sliding and static friction, for many surfaces, static friction can often generate higher forces. The on/off hurky jerky motion of crawl may look archaic, but it's likely by design and what enables the system to crawl out of situations like being buried in sand.

One area where physical lockers help is that it is not reactionary and pre-empts situations, like keeping momentum. Whereas other traction aids only step in once some momentum is lost and it's recognized a situation where it needs to appropriate power.

ATRAC is another on the fly traction aid in the 200-series. I was surprised how great it works with a rear locker and how quickly it acts. The later 200-series upgrades with MTS probably do even better. In this particular climb up moguls, as soon as the front tire lifts, ATRAC is acting immediately to maintain power to the other loaded front tire. Almost makes a front locker arguably necessary, but I'm sure there's hard core rock crawlers where that has benefits too.

@19 seconds. No sound in this as it was drone video

 
As far as I know (and I don't know a lot), LX 570 have the center diff. lock which I believes that means split power between rear and front wheels 50/50 only. This does not mean rear and the front wheels are locked, correct? I still have limited-slip lock in the rear and front, right?

I’m sure most of the people in this thread know, but since the OP was asking about general differential functions, it should be pointed out that the center differential is a Torsen LSD type. So when not locked it’s not also fully open. I believe it’s somewhere around 60%tear/40% front biased when not slipping.
 
But if three tires are slipping 100% goes to one wheel...
 

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