Situations off road when you should leave center differential unlocked?

[Reconvened]

Hey guys, I have a 2001 LX470 with ATRAC. After my recent experience off road, where i had a very tough time ascending a muddy/slippery sharp inclined hill, i was wondering whether it might have somehow been beneficial (as far as ATRAC is concerned) to leave the center diff unlocked. Maybe it would give the ATRAC system more options on where to redistribute the power? Just wanted to get your guys thoughts on this.

Thanks!

 

[MountaineerLC]

While there are a few exceptions, basically never. Locking the center forces a 50/50 split front to rear. For example, if a front wheel is spinning, the rear remains unaffected. On the other hand, with the center unlocked, loss of traction at one tire can case a loss of traction to all 4. I had a 2000 LR Disco II once upon a time and wheeled it in its stock configuration for years. (electronic traction control and open diffs all around) After several years of ownership I learned that the center diff was lockable, but LR, in their infinite wisdom, didn't include a mechanism to lock it. I eventually rigged a lever that would allow me to lock the center. Traction improved substantially and I never encountered a situation where I felt the vehicle performed better unlocked.

ATRAC and other electronic traction control systems are great, but no match for mechanical lockers (especially the center), IMO.

 

[ramangain]

While there are a few exceptions, basically never. Locking the center forces a 50/50 split front to rear. For example, if a front wheel is spinning, the rear remains unaffected. On the other hand, with the center unlocked, loss of traction at one tire can case a loss of traction to all 4. I had a 2000 LR Disco II once upon a time and wheeled it in its stock configuration for years. (electronic traction control and open diffs all around) After several years of ownership I learned that the center diff was lockable, but LR, in their infinite wisdom, didn't include a mechanism to lock it. I eventually rigged a lever that would allow me to lock the center. Traction improved substantially and I never encountered a situation where I felt the vehicle performed better unlocked.

ATRAC and other electronic traction control systems are great, but no match for mechanical lockers (especially the center), IMO.

Infinite wisdom = penalize you for not buying the Range Rover

 

[Bisho]

I’ll unlock if I anticipate a tight turn or when on pavement, of course.

 

[nukegoat]

The vast majority of boring dirt roads do not require the cdl

 

[MechE30]

Andrew St Pierre White says to always lock it. That’s good enough for me.

 

[ramangain]

Who?

Edit: I Googled him. Ok.

 

[Mike NXP]

Andrew St Pierre White says to always lock it. That’s good enough for me.

I've seen that as well and think about it often as I am barreling down the rocky dirt roads BUT generally speaking I'd rather have my stability control working then all 4 wheels locked.

Now-a-days I only seem to lock my CDL just to give it a little work out now and then OR if I am on some really loose terrain / hill climbing moving low and slow.

This especially proves true in winter time around here, the roads turn to hard pack ice and as I am slipping around corners I'm happy to have my traction control do it's thing. I guess on the flip side If I had the CDL locked I wouldn't slip as much but yeah, just one idiots opinion.

 

[KliersLC]

I've seen that as well and think about it often as I am barreling down the rocky dirt roads BUT generally speaking I'd rather have my stability control working then all 4 wheels locked.

Now-a-days I only seem to lock my CDL just to give it a little work out now and then OR if I am on some really loose terrain / hill climbing moving low and slow.

This especially proves true in winter time around here, the roads turn to hard pack ice and as I am slipping around corners I'm happy to have my traction control do it's thing. I guess on the flip side If I had the CDL locked I wouldn't slip as much but yeah, just one idiots opinion.

This.

Also, on tight trails with lots of traction, and especially on tight turns facing down hill on ice or mud. With the CDL engaged, it will tend to push the front end through the corner and over the bank.

As to your original situation, I have wondered the same thing and thought the ATRAC might have more traction options with the CDL off, but while I think that is technically true, I don't think the technology in these old trucks makes that actually the case. I've done the same hill climb back to back with CDL off and on, and the LX performed better with the CDL on. So, in that case anyway, the theoretical advantage did not translate into actual capability. Maybe on Ice or sand it could be different... dunno.

 

[Mike NXP]

This.

Also, on tight trails with lots of traction, and especially on tight turns facing down hill on ice or mud. With the CDL engaged, it will tend to push the front end through the corner and over the bank.

As to your original situation, I have wondered the same thing and thought the ATRAC might have more traction options with the CDL off, but while I think that is technically true, I don't thing the technology in these old trucks makes that actually the case. I've done the same hill climb back to back with CDL off and on, and the LX performed better with the CDL on. So, in that case anyway, the theoretical advantage did not translate into actual capability. Maybe on Ice or sand it could be different... dunno.

Yeah for sure. If these forums and trail riding have taught us anything it's that every situation is different and calls for a different action.

 

[Lonegrasshopper]

The vast majority of boring dirt roads do not require the cdl

Vast majority of 1996 Honda Accords are fine on boring dirt roads.

 

[MountaineerLC]

I've seen that as well and think about it often as I am barreling down the rocky dirt roads BUT generally speaking I'd rather have my stability control working then all 4 wheels locked.

Now-a-days I only seem to lock my CDL just to give it a little work out now and then OR if I am on some really loose terrain / hill climbing moving low and slow.

This especially proves true in winter time around here, the roads turn to hard pack ice and as I am slipping around corners I'm happy to have my traction control do it's thing. I guess on the flip side If I had the CDL locked I wouldn't slip as much but yeah, just one idiots opinion.

I recall Andrew saying that once, but in hind sight I believe he was referring to part time 4wd not AWD/4wd like our 100's. Obviously being in 4x4 would be superior to being in 4x2.