Thread: When to lock CDL

Originally Posted by strangy

I’m not sure what to do now.
Is there a risk of inadvertent air bag deployment by over usage of the CDL or could it be the other way around?
When I engaged the CDL last time my passenger started to whine and I was concerned as didn’t want to experience driver wind up from CDL overuse.
Looking back I think that not using the CDL when I should have may have contributed to radio stations being out of reception earlier than when CDL wasn’t engaged.
I’ve fixed a few of these things but am still unsure if the CDL may be contributing to the wear on the shift lever knob.
I’m also concerned that uni joints will wear prematurely.
Maybe this is affecting my overall aging process too.
Any help greatly appreciated.

Really
Don`t add more fuel to the fire FFS

Strangy. That's funny. I love the 'wear on the shift lever knob' bit. Sarcasm par excellence...

Amazing thread. I am reminded of one where I took a position on mechanical advantage. Pretty much everyone who posted was saying the same thing, but apparently I was speaking Klingon.

The OP was concerned about windup, IIRC. Here's a test. Your car will have a 4WD light of some kind. Engage the CDL in the manner you describe. Drive the car on the roads/tracks you encounter. When you get back to the bitumen, disengage the CDL. Watch to see when the light goes out. Perhaps you could accel/decel, or steer left and right a bit. If the light doesn't go out you have windup. Stop and reverse a little. If it doesn't go out then you have windup to be concerned about.

I am in the camp of engage CDL on loose surfaces. In my D1 it seems to stabilise the car. When I was driving my D2 I don't think I bothered, but the D2 was always more stable in a general sense ( it's been some time since I drove my D2 ). However, as someone else said, if it is good enough for Dave Ashcroft, it's good enough for me.

Another thing I would say: if a thread becomes boring to individuals, I would ask; why are you reading it? Even more, why are you contributing ( or not )? It makes no sense. Move on.

Originally Posted by rangieman

Really
Don`t add more fuel to the fire FFS

Actually, Chris, I reckon Strangy nailed it. No /sarc tag required.

" Another example of where the ATB would help would be when rapidly changing from high to low traction surfaces, *i.e. when driving on snow or ice,

In both of these examples the ATB will limit the amount the difference in propshaft speed and transfer torque to the axle with traction.

The two big advantages are increased traction when unlocked and eliminating the weakness of the stock unlocked centre diff." Ashcroft


Thats what an atb does in the centre diff. So yes i didnt have to lock the centre diff as the atb would automatically transfer torque to the axle with the most traction or least propshaft speed. In other words drive would be sent to the axle that had no wheels spinning or the least propshaft speed. This is safer than using the standard cdl unlocked and a good compromise between high traction and low traction surfaces. To the average Joe locking the centre diff on dirt is just playing it safe.

You dont have to agree and I dont want anyone to agree for the sake of it, simply my opinion. However i bought a 4wd to transport me and my faimly safely to places. Never had an issue with a locked cdl, never lost vehicle control never understeered as some claim and the "wind up" issue was so bad that i dont know how the car didnt blow up...not!

The problem at hand is what constitues a high traction surafce and i argue that anything that is not a man made covered surface will be lower traction hence engaging true 4wd is the safest bet.

Andrew st Pierre recomends it, Bruce Davis recomends it, 4x4 Australia recomends it...but eh....people on this forum seem to know better.

I had to sell the 110 to buy a family friendly vehicle so i bought a Patrol. I put it in 4wd every time it touches the dirt or any surface with less traction than that of a man made surface like i did the 110. I just dont know why i havent "understeered" into a tree or lost control.....the other thing i dont understand is how all this wind up hasnt ever blown up my drive train on any vehicle???? Its got me puzzled; 🤣🤣🤣🤣not! If there was ever going to be a vehicle where wind up was an issue the independent y62 with 400hp and weighing 3 tons would be it.....

What i have seen is the result of people loosing control of their vehicle when they've lost traction or encountered unexpected terrain. Kind of going to happen when your on dirt road with no guarantee of surface quality. You learn to apprecaite surface quality when you ride motorbikes, even more so when u come off them.

Ps: the definiton of insanity is correct! so one more video. The first 4 minutes say it all and from 10 minutes also! Enjoy
YouTube

Originally Posted by 1nando

" Another example of where the ATB would help would be when rapidly changing from high to low traction surfaces, *i.e. when driving on snow or ice,

In both of these examples the ATB will limit the amount the difference in propshaft speed and transfer torque to the axle with traction.

The two big advantages are increased traction when unlocked and eliminating the weakness of the stock unlocked centre diff." Ashcroft.

All the above is correct. But as always “a text without a context is a pretext”.

The context for those remarks (found elsewhere in the same Ashcroft web page) is that all the above is correct “within certain limits” of the ATB to function as above.

That limitation is regards when one wheel (or one prop shaft, in respect to centre diff) can spin up way more then the other side.

My points stand. You could easily spin up a front and/or a rear wheel with centre ATB unlocked. The ATB action falls away to behave like an open diff.

The amazing thing thing is that the ATB action works just as well when wheels on BOTH sides are on ice, or BOTH sides are on tarmac. Ie a rear axle with ATB will handle both rear wheels being on ice. But when one is on tarmac/rock/gravel and the other is on ice - game over. The difference in available traction across the device means it functions only as an open diff.

By your logic - you may we’ll be lucky to be alive driving dirt roads with an unlocked centre ATB! Because if things turned to custard, an off camber bend, slightly uphill, a little rut your inside front wheel traverses and loses all traction. Your pro reflexes dulled or distracted a moment .... that front wheel, wheelspins up. Your ATB says “I’m a teapot!”

You are then then as much a dead duck as you think the poor folks with just an unlocked OPEN diff would be in that situation.

Your videos still do not address these simple facts. Apples and oranges. Pretexts without context.

Beats me how people like Len Beadell survived opening up the country they did, with nowt but a Series 1 or 2 Landy, with no CDL, and open diffs. Traction must've been different back then

Originally Posted by donh54

Beats me how people like Len Beadell survived opening up the country they did, with nowt but a Series 1 or 2 Landy, with no CDL, and open diffs. Traction must've been different back then

Those days they didn't have to worry about buggering up the CDL because they didn't have one.
The Main reason why I lock my CDL on the loose stuff is to prevent destroying it, The added handling/traction is just a bonus