Center differential not unlocking?

[MileHigh]

Was out on some dirt and muddy roads, so I thought I’d try locking the center differential. Not sure I really needed it. Just wanted to try it. When I got back to pavement, I disengaged the center lock. But it kept on saying it was locked? It was a long straight road. I tried engaging the center lock and disengaging it. No effect I pulled over and with it unlocked cycled the engine and that didn’t change the locked state. It wasn’t until I got to a place where I could do some U-turns that it indicated it wasn’t locked.

Is that normal?

Next time I won’t get off the dirt road until I get an unlock indication.

I put the off-road display on to monitor Temps. As a side question , what are maximum temperatures, and standard temperatures for the various parts of the powertrain.

In one of the third-party videos they mentioned, but did not explain saying that they over tempt one of the front or rear differentials when it was locked. I didn’t know this was really possible?

 

[CRH]

The front and rear lockers need a bit of turning so it registers that it isn't locked. The lights stay on even though unlocked until it can tell that they are definitely unlocked. Maybe this was the same issue with you being on a straight road?

 

[Ovrland Bill]

I have had the same difficulty ‘unlocking’ the center differential. Staying off of the pavement while employing the old Land Rover technique of reversing the vehicle eventually solved the problem. Perhaps further use will ‘loosen things up’…

 

[singlefin]

I think what you’re experiencing is normal and it’s better to get unlocked while you’re still on low friction surfaces. Center diff for me locks and unlocks pretty quickly but I cycle steering L/R with a little throttle or reverse a few feet. Sometimes all is aligned and lock and unlock happens within a sec others might need bit of deliberate action.

I don’t like the transfer case knob, needs to be solid and have a little weight to it.

 

[anand]

If you're on a straight road, and going straight, all four wheels (or in this case, specifically the general speed of the front and rear axles) will be moving at the same speed. The process of locking and unlocking requires some difference in speed between the two parts that are attempting to be connected or disconnected. Thus why it didn't actually disconnect until the U-turn (at which point the axle speeds were different).

When driving straight, it doesn't make a bit of difference (in terms of wear/damage/concern) if the diffs (any of them) are locked or unlocked as all four tires are moving at the same speed (assuming traction is plentiful).

Hopefully this helps to explain it a bit more

 

[Jiman01]

I’m not sure I follow. The center diff is a manual cable actuated shift over to High or Low/locked unlocked. I don’t think cycling the engine will change anything.

Are you saying you shifted over using the transfer case lever (ball shifter) and when you shifted by back to, presumably unlocked/High, it didn’t work?

If it shifted back, the blinking Telltail light you’re probably seeing will eventually disappear, but the important part is that it engaged. If the shifter is in the high/unlocked position (top left corner), you should be go to go. If you got a bunch of grinding sound then you’re not and should try again

It also might be worth mentioning that the transfer case works in a box pattern. According to the brief I got at delivery, you shouldn’t shift diagonally, ie from unlocked/high to locked/low or unlocked low/locked high.

 

[Logsplitter]

Was out on some dirt and muddy roads, so I thought I’d try locking the center differential. Not sure I really needed it. Just wanted to try it. When I got back to pavement, I disengaged the center lock. But it kept on saying it was locked? It was a long straight road. I tried engaging the center lock and disengaging it. No effect I pulled over and with it unlocked cycled the engine and that didn’t change the locked state. It wasn’t until I got to a place where I could do some U-turns that it indicated it wasn’t locked.

Is that normal?

Next time I won’t get off the dirt road until I get an unlock indication.

I put the off-road display on to monitor Temps. As a side question , what are maximum temperatures, and standard temperatures for the various parts of the powertrain.

In one of the third-party videos they mentioned, but did not explain saying that they over tempt one of the front or rear differentials when it was locked. I didn’t know this was really possible?

I find the lever moves easily between the centre diff locked and unlocked position but as others have said the diff will stay locked until the axles move at different speeds. Try steering from right to left as you slowly go forwards or backwards and the diff will unlock itself. It is normal to have to do this.
On my old Hilux I always had to reverse up and steer from left to right a few time a before it would come out of four wheel drive and back into two wheel drive as gears had bound up a bit.

 

[MileHigh]

It’s been a couple of weeks, but I don’t remember any grinding at any transfer, and I was only going lock/unlock in high.

I just did the start/stop/‘re-boot’ because I was able to pull over and it gave me a chance to confirm what the manual said.

I subscribe to the theory that the lockers are actually locking and unlocking, it is just that the sensing system is going to tend to indicate that it ISN’T unlocked, even though it is- since the error the other way is actually far more potentially damaging. I think there was a recent review where the front locker is indicating that is still locked, but by the spin of the wheels across the axel, the locker definitely isn’t locked.

The center locker is a lot harder to determine by performance if it is locked. That is why I was asking about temps. I assume that the center diffs temp would rise if used on regular pavement.

In the past in off-roading the lockers have locked and unlocked pretty fast, so this surprised me.

On the use of the center locker, I was just playing around with it- but I am still unclear on the best use scenario. Using the locker turns of ‘some’(?) of the ESC functions. So I’m trading some electronic stability for mechanical drive.

So the first thing is that you’d be driving faster and have more traction than getting into 4Lo.
And if you are travelling at a higher (highway) speed(?), you’d leave the center open and use the ESC for better stability.
If traction, conditions and speeds are in between those two, then you’d use the center lock.

So if traction and conditions are bad, and you’ll stay under 20mph- 4Lo/center locked, with axle lockers as needed.
20-45mph, 4hi with center locked
45+ 4HI, no center lock, and let stability control keep the headlights forward.

Mountain ski traffic get crazy here in CO. 10,000Ft+, 10F, with blowing snow, with snow and some ice on the road- with inclines and declines with 70+mph speeds at times with minimal following distances. Swiss Alps meets I-294 in Chicago. We aren’t in Kansas anymore.

 

[Logsplitter]

I don’t think using the centre diff lock in high range disables the ESC unless you use off road mode.
When driving on dirt/ gravel roads at speed I tend to use centre diff locked.

 

[singlefin]

20-45mph, 4hi with center locked
45+ 4HI, no center lock, and let stability control keep the headlights forward.

Mountain ski traffic get crazy here in CO. 10,000Ft+, 10F, with blowing snow, with snow and some ice on the road- with inclines and declines with 70+mph speeds at times with minimal following distances. Swiss Alps meets I-294 in Chicago. We aren’t in Kansas anymore.

I haven't monitored the temps to note if transfer case temp rises after being locked. I'd suspect it would be negligible w/ transfer case locked.

When you lock the center diff ESC switches to ESC off-road which has delayed interruption. ESC is normal in 4Hi unlocked. Problem with letting ESC keep headlights forward is you might not want that when it activates in a corner or turning off the road. In general ESC tends to be okay in the snow with driving mellow but if you have an inner rally driver I wouldn't be surprised if normal ESC is found annoying. I don't see a concern driving center diff locked 65mph +/- in slick conditions.

The I70 race is one I'm glad I don't have to partake in.

 

[Logsplitter]

Are you sure that having the centre diff locked means that ESC off road is enabled. I thought ESC was still active until you engaged off road mode this then enables ESC offroad

 

[Jiman01]

The center locker is a lot harder to determine by performance if it is locked. That is why I was asking about temps. I assume that the center diffs temp would rise if used on regular pavement.

In the past in off-roading the lockers have locked and unlocked pretty fast, so this surprised me.

Mountain ski traffic get crazy here in CO. 10,000Ft+, 10F, with blowing snow, with snow and some ice on the road- with inclines and declines with 70+mph speeds at times with minimal following distances. Swiss Alps meets I-294 in Chicago. We aren’t in Kansas anymore.

IMO, the easiest, quickest way to determine if you’re in gear is to shift, let go of the collar, and shake the shifter similar to what you’d do to make sure you were in neutral using a manual transmission. If the transfer case is in the gear selected, it will stay in the position. If it’s not, you’ll feel it slip out and it will sorta be between corners of the box shape mentioned earlier…hopefully that makes sense.

If it doesn’t engage, move forward or back a bit and try again to better match the gears. I personally haven’t tried shifting the transfer case while moving.

The other thing that was told to me is NOT to put it in Park if you’re not in H/unlocked…always put it in Neutral and use the hand brake.

Haven’t been back to CO to ski but used to go every year with the family. I70 is crazy and you’re not kidding about the speed, steep slopes, following distance, and road conditions. I literally saw a G-Wagon, who was following me too closely, do multiple barrel rolls after I took an exit. The G-Wagon didn’t realize it was an exit (because visibility was bad and they were following so closely) and tried to get back on I70.

I couldn’t stop to help because there was literally a wall of snow on either side so the best I could do was call 911.

 

[MileHigh]

I haven't monitored the temps to note if transfer case temp rises after being locked. I'd suspect it would be negligible w/ transfer case locked.

When you lock the center diff ESC switches to ESC off-road which has delayed interruption. ESC is normal in 4Hi unlocked. Problem with letting ESC keep headlights forward is you might not want that when it activates in a corner or turning off the road. In general ESC tends to be okay in the snow with driving mellow but if you have an inner rally driver I wouldn't be surprised if normal ESC is found annoying. I don't see a concern driving center diff locked 65mph +/- in slick conditions.

The I70 race is one I'm glad I don't have to partake in.

That is what I hope, and it is probably doing. Keeping you spinning out, physics limited.

Are you sure that having the centre diff locked means that ESC off road is enabled. I thought ESC was still active until you engaged off road mode this then enables ESC offroad
View attachment 7881184

Center diff will light up a warning on the idiot board about ESC. Now how that mode differs from full Off road, I’m not sure. I thought off road would turn it off, but if you don’t have lockers, I could still see wanting some ESC in even 4 low center locked- if you can’t lock your axles. The various interactions of of road ESC in my 2000s Grand Cherokee’s were wicked useful.

IMO, the easiest, quickest way to determine if you’re in gear is to shift, let go of the collar, and shake the shifter similar to what you’d do to make sure you were in neutral using a manual transmission. If the transfer case is in the gear selected, it will stay in the position. If it’s not, you’ll feel it slip out and it will sorta be between corners of the box shape mentioned earlier…hopefully that makes sense.

If it doesn’t engage, move forward or back a bit and try again to better match the gears. I personally haven’t tried shifting the transfer case while moving.

The other thing that was told to me is NOT to put it in Park if you’re not in H/unlocked…always put it in Neutral and use the hand brake.

Haven’t been back to CO to ski but used to go every year with the family. I70 is crazy and you’re not kidding about the speed, steep slopes, following distance, and road conditions. I literally saw a G-Wagon, who was following me too closely, do multiple barrel rolls after I took an exit. The G-Wagon didn’t realize it was an exit (because visibility was bad and they were following so closely) and tried to get back on I70.

I couldn’t stop to help because there was literally a wall of snow on either side so the best I could do was call 911.

Yea, I got the selector to move and ‘lock’.

Interesting intel on the use of neutral and handbrake. I remember a discussion about using the winch and gear settings.

I70 is nuts. I can’t imagine what it was like before the Eishower tunnel and EFI engines. Wife’s family had a supercharger put on their Suburban in the late 70s as all the crappy carberated and anemic cars struggled. Rental and Texas cars are always to be avoided when it starts to get slickery. Have had fog turn to ice on the whole I-70 coming down in the front range. Terrifying.

 

[Logsplitter]

Does left foot braking work if you don’t have ESC when using 4lo centre diff locked.

 

[landmannnn]

I think we are confusing Electronic Stability Control with Traction Control.

While they sort of do a similar thing...

ESC recognises if you are going too fast around a corner and applies the brake to a specific wheel to prevent oversteer or understeer. It appears to be less active in low, as you would expect as the speed is far less.

Traction Control recognises a wheel spinning due to loss of traction and applies the brake to that wheel.

ESC is turned off when the Off Road button is depressed or axle diff locks are applied. TC is on all the time, except that it is also switched off when the axle difflocks are applied.

 

[singlefin]

Are you sure that having the centre diff locked means that ESC off road is enabled. I thought ESC was still active until you engaged off road mode this then enables ESC offroad
View attachment 7881184

believe so from these two snips out of the manual.

 

[singlefin]

I think we are confusing Electronic Stability Control with Traction Control.

While they sort of do a similar thing...

ESC recognises if you are going too fast around a corner and applies the brake to a specific wheel to prevent oversteer or understeer. It appears to be less active in low, as you would expect as the speed is far less.

Traction Control recognises a wheel spinning due to loss of traction and applies the brake to that wheel.

ESC is turned off when the Off Road button is depressed or axle diff locks are applied. TC is on all the time, except that it is also switched off when the axle difflocks are applied.

ESC is how we interact with traction control. TC is informed by ESC and uses ABS and control of throttle position to do its job. It can’t do anything when ESC and ABS off.