How necessary is CDL really?

[TCH2FLY]

@TCH2FLY , your DP looks scary. Is it real?

LOL no. It's a real spot in Moab but that is mostly photoshop, the overhang actually ends about 2' in front of the rig so I am well behind it ... the original is here

Ding Ding Ding .... we have a winner!

It is on Porcupine Rim at Moab.
Here is the original

 

[rlynch356]

I'd fix it.... a CDL is critical in a Full time 4WD system. You do need to know when and how to use it.
It is different from Part time 4WD systems like the Tacoma, Jeep, etc.. when you put those in 4WD it locks in the front axle distributing power/torque 50/50 front to rear.
Open Diffs will always allow power to the path of least resistance i.e. the wheel with the lowest grip.
A-TRAC uses the brakes and engine computer to modulate torque delivery to the wheel(s) with the most grip, and it does this Front to rear as well as side to side.
It will shut down with heat since it uses the brakes to work... something to be aware of when using it.
A locker, distributes power/Torque to both wheels 50/50 which is what makes them effective. Also it does not limit torque

 

[mcgaskins]

Interesting discussion here. For the first ~12 years I was wheeling, I owned Jeeps that had part time transfer cases - meaning, they were either in rear wheel drive or four wheel drive with no center diff lock. When you switched from 2wd to 4wd high or low, it was permanently locked 50/50 front to rear, and I had no personal experience with a selectable center differential and had not owned a full time 4wd drive system until about 11 years ago.

Since I bought a 100 in 2012, I've pretty much only driven full time 4wd systems with a selectable center diff switch, and I have to say I much prefer it because it simply offers more options for controlling where power goes. I have a less common driving style when it comes to actually using the CDL however, which is to say I rarely lock mine, and when I do lock it, I unlock it after it's needed much like the rear ARB differential locker I have on my 2013 200. Here's my view: the typical torque split front to rear is 40/60, and when you are climbing (particularly in high traction situations like in slickrock), the weight of the vehicle naturally transfers towards the rear axle. How much weight is transferred depends on many factors of course, but that also means less weight is on the front axle. If the CDL is unlocked, that means more torque is being applied to the axle with more weight on it which means more traction (especially helpful in the rear diff is locked) and conversely less torque is transferred to the axle with less traction. When I get to the top of the hill and have to descend, it's also more helpful to leave the CDL unlocked because there is less drivetrain bind and letting the limited slip do its thing means smoother turns without wheel chatter.

Of course there are plenty of scenarios where it's beneficial to lock the CDL as well like long, loose, steep climbs where traction is low. It can be helpful in snow (easiest way to do sweet doughnuts in a parking lot btw), rainy/slippery trails, etc., but I prefer to nearly always leave it unlocked on descents or when very tight turning is needed. On the descent of Black Bear Pass or any tight switchbacks for that matter, having the CDL unlocked is the difference between a potential 1 point to 2 or 3 point turn. I prefer to make the turn with as little reversing as necessary because it's easier on the vehicle and easier on the trail - provided you don't swing too far to the edge and create erosion of course.

I know it's a very common adage to lock the CDL as soon as you hit dirt, and that's exactly what I did for many years wheeling Jeeps because I had no choice. The 200 gives us a choice though, so I think it's important to safely experiment with different methods and see what works best for various scenarios. For me, that often means leaving the CDL unlocked until I need it then locking it only for as long as I need it.

 

[TCH2FLY]

Interesting discussion here. For the first ~12 years I was wheeling, I owned Jeeps that had part time transfer cases - meaning, they were either in rear wheel drive or four wheel drive with no center diff lock. When you switched from 2wd to 4wd high or low, it was permanently locked 50/50 front to rear, and I had no personal experience with a selectable center differential and had not owned a full time 4wd drive system until about 11 years ago.

Since I bought a 100 in 2012, I've pretty much only driven full time 4wd systems with a selectable center diff switch, and I have to say I much prefer it because it simply offers more options for controlling where power goes. I have a less common driving style when it comes to actually using the CDL however, which is to say I rarely lock mine, and when I do lock it, I unlock it after it's needed much like the rear ARB differential locker I have on my 2013 200. Here's my view: the typical torque split front to rear is 40/60, and when you are climbing (particularly in high traction situations like in slickrock), the weight of the vehicle naturally transfers towards the rear axle. How much weight is transferred depends on many factors of course, but that also means less weight is on the front axle. If the CDL is unlocked, that means more torque is being applied to the axle with more weight on it which means more traction (especially helpful in the rear diff is locked) and conversely less torque is transferred to the axle with less traction. When I get to the top of the hill and have to descend, it's also more helpful to leave the CDL unlocked because there is less drivetrain bind and letting the limited slip do its thing means smoother turns without wheel chatter.

Of course there are plenty of scenarios where it's beneficial to lock the CDL as well like long, loose, steep climbs where traction is low. It can be helpful in snow (easiest way to do sweet doughnuts in a parking lot btw), rainy/slippery trails, etc., but I prefer to nearly always leave it unlocked on descents or when very tight turning is needed. On the descent of Black Bear Pass or any tight switchbacks for that matter, having the CDL unlocked is the difference between a potential 1 point to 2 or 3 point turn. I prefer to make the turn with as little reversing as necessary because it's easier on the vehicle and easier on the trail - provided you don't swing too far to the edge and create erosion of course.

I know it's a very common adage to lock the CDL as soon as you hit dirt, and that's exactly what I did for many years wheeling Jeeps because I had no choice. The 200 gives us a choice though, so I think it's important to safely experiment with different methods and see what works best for various scenarios. For me, that often means leaving the CDL unlocked until I need it then locking it only for as long as I need it.

I started wheeling the same way but I even drove early split shift setups with a 2wh and 4wh lever and a hi-lo lever before getting a single lever. I never had issues getting where I was going and never felt the need for locking axle diffs until I decided to do the Rubicon. I am impressed with my 200 but differ in that I still prefer a part-time system for off-roading any tougher than forest service roads or moderate Moab trails.
That is not meant to say that the 200 isn't capable, the Torsen center diff is magnitudes better than the VC in the 80 series (why mine in now gone and is a part time system).
The system is well engineered and with an unlocked CDL the 200 will go 90% of the places you point it (or should point it) and then the overall size and amount of modifications become the limiting factor.

All that said I am on the fix it side ... #1 it will never get cheaper to fix and #2 it will be a harder sell should you want to part ways with it.

 

[Bunga]

In moderate terrain it really doesn't matter. In anything serious climbing, I need it because A-trac even in "rock" will not let you keep climbing without it. Just fix it, easy to do yourself.

 

[NYC570]

I started wheeling the same way but I even drove early split shift setups with a 2wh and 4wh lever and a hi-lo lever before getting a single lever. I never had issues getting where I was going and never felt the need for locking axle diffs until I decided to do the Rubicon. I am impressed with my 200 but differ in that I still prefer a part-time system for off-roading any tougher than forest service roads or moderate Moab trails.
That is not meant to say that the 200 isn't capable, the Torsen center diff is magnitudes better than the VC in the 80 series (why mine in now gone and is a part time system).
The system is well engineered and with an unlocked CDL the 200 will go 90% of the places you point it (or should point it) and then the overall size and amount of modifications become the limiting factor.

All that said I am on the fix it side ... #1 it will never get cheaper to fix and #2 it will be a harder sell should you want to part ways with it.

Why do you prefer a part time system for off-roading?

 

[TeCKis300]

Why do you prefer a part time system for off-roading?

Ability to hang the rear end out and do donuts!

 

[TCH2FLY]

Why do you prefer a part time system for off-roading?

Well I prefer it for all driving ( I have owed AWD cars) but it really is a simple as either I need 4wd or I don't and feel like the unlocked full time system is like sort of needing 4wd. I had a Tacoma Pre-runner (2wd) with a rear locker and drove a lot of trails and the only downside was a lack of a low crawl gear ... not the lack of 4wd. I learned to drive at 10 years old on our ranch in a 2wd Ford PU with granny low 1st and had to learn how to keep from getting stuck in the fields and pastures to avoid the humiliation of walking home to get the tractor to pull it out. I didn't get my first 4x4 till my mid 20s and up to then I always got around in snowy CO winters by having good tires and learning good driving skills. My sports car has a manual trans ... I'm an analog kind of guy, I like the engagement with the vehicle, in control not along for the ride.

Look at it this way Toyota engineers know that maximum traction requires the center diff to be locked so they have a switch, the rest of the time it is less than maximum traction which is fine but most useful in slick/slippery/varying on-road situations where locking the front and rear together is less desirable. The Torsen system is great under those conditions preventing drivetrain wind up and potentially under/oversteer situations.

 

[Sinister]

I always use it on the beach and if I think the snow is a little to deep on the roads. Other than that, its off.

 

[NYC570]

Well I prefer it for all driving ( I have owed AWD cars) but it really is a simple as either I need 4wd or I don't and feel like the unlocked full time system is like sort of needing 4wd. I had a Tacoma Pre-runner (2wd) with a rear locker and drove a lot of trails and the only downside was a lack of a low crawl gear ... not the lack of 4wd. I learned to drive at 10 years old on our ranch in a 2wd Ford PU with granny low 1st and had to learn how to keep from getting stuck in the fields and pastures to avoid the humiliation of walking home to get the tractor to pull it out. I didn't get my first 4x4 till my mid 20s and up to then I always got around in snowy CO winters by having good tires and learning good driving skills. My sports car has a manual trans ... I'm an analog kind of guy, I like the engagement with the vehicle, in control not along for the ride.

Look at it this way Toyota engineers know that maximum traction requires the center diff to be locked so they have a switch, the rest of the time it is less than maximum traction which is fine but most useful in slick/slippery/varying on-road situations where locking the front and rear together is less desirable. The Torsen system is great under those conditions preventing drivetrain wind up and potentially under/oversteer situations.

Yes, I thought it was weird that someone would prefer a part time system for off-road. I understand for on-road conditions.

 

[Fisher23]

Yes, I thought it was weird that someone would prefer a part time system for off-road. I undertand for on-road conditions.

It depends on how loose the offroad is. If it's frozen I would leave it off.

 

[rlynch356]

I think, we are getting into a lot of mixed up terms here...
anyway...

its always good to invest in training for the driver on how to use the systems your truck comes with, and when to use what, and what its for....

I'll leave it at that.

 

[TeCKis300]

I think, we are getting into a lot of mixed up terms here...
anyway...

its always good to invest in training for the driver on how to use the systems your truck comes with, and when to use what, and what its for....

I'll leave it at that.

I've learned a lot from those before me. Please do share.

 

[manofthewoods]

In moderate terrain it really doesn't matter. In anything serious climbing, I need it because A-trac even in "rock" will not let you keep climbing without it. Just fix it, easy to do yourself.

A nice one paragraph synopsis.
A) fixing it should be easy
B) I drive my 80 series off road almost every day (for my dogs).
I can walk through deep sand in 4H just using the standard viscous coupler. With my 200 I think the TORSEN is even better. Haven't needed the CDL on the 200, but I like it to be in good working order when/if I do need it.

 

[onelittlestar]

Troubleshooting link for CDL, I use this site all the time...may not be relevant past 2013

Transfer case

 

[linuxgod]

Troubleshooting link for CDL, I use this site all the time...may not be relevant past 2013

Transfer case

That’s the FSM data. Problem is when this happens you won’t find any issues. Something else is up

 

[onelittlestar]

That’s the FSM data. Problem is when this happens you won’t find any issues. Something else is up

I need to dig in myself, can’t shift into 4Lo or activate CDL

 

[ryanCA]

My 08 has not been offroaded in its life till I bought it.

4lo - works perfect , I can feel the gearing

CDL - when you press button - works perfectly (I think ) - the light is solid. It doesnt feel different

But when I turn it off, light will blink forever. Reverse, forward, light doesnt go off. Keeps blinking. Turning car off and on- turns light off for good. no more blinking

I changed the fluid. Went offroad again. Same above behavior. Turns on instantly, but turn off light is all flashing, till I turn car on and off

 

[MCtree]

I often use the CDL on my LCs and miss it when I don’t have it. Borrowed my buddies 2023 Tacoma TRD Sport a couple of weeks ago to drive the beach here in Homer to gather coal for this winter. I usually just use the 100 but he offered and it would mean less trips because of the larger Tacoma bed. Anyways I got stuck in soft sand of the type that has never troubled me before. 4WD low and airing down made no difference. The CDL would have helped as I basically had 2WD with the open diffs front and rear and low traction. Finally jammed enough driftwood under all 4 tires to get out. Wish i had the CDL and learned the TRD Sport trim doesn’t have it.

Sorry. Late to this thread…. But can you expand on the “gather coal for this winter” on the beach?

Gather wood and make charcoal?
Is there actual coal on the beach?
I’m befuddled and as a wanna-be Alaskan I am curious about the natives.

 

[MCtree]

No matter - it doesn’t help. Glad for drift wood.

Ah… never mind.
I should have read on.