Unlocking centre diff in low range

[Drew Advanced Member Find all posts View Profile Close Drew]

I'm interested whether it's possible to modify the system so I can unlock the centre diff when I select low range.

I think it would be handy when reversing up steep driveways (like mine) and when manoeuvring caravans and trailers and the like. The sorts of situations I'm thinking of are, obviously, on a grippy road surface like concrete or bitumen.

Does anyone know if this has been done before - I read somewhere about a this mod being done in a 80 or 100 series.

Cheers,

Drew.

[Drew Advanced Member Find all posts View Profile Close Drew]

Might have answered my own question - the Factory Manual refers to an actuator on some models, I guess this is for those models that have a centre diff lock switch, whereas my vehicle relies on a mechanical process to lock the diff when the transfer lever is thrown.

It's too late and it's been a long day..........

Drew.

[quadcam Junior Member Find all posts View Profile Close quadcam]

I've been thinking about this too as my previous vehicle (Discovery) had the ability to run low range unlocked or locked and it was handy sometimes. I have a manual which shows cutaways of both transfer cases. I haven't looked for a while but recall that while it shouldn't be too hard (internally) to remove the lock function from the existing lever it would require the electronic lock from the other case to be fitted.

[Drew Advanced Member Find all posts View Profile Close Drew]

I've been thinking about this too as my previous vehicle (Discovery) had the ability to run low range unlocked or locked and it was handy sometimes. I have a manual which shows cutaways of both transfer cases. I haven't looked for a while but recall that while it shouldn't be too hard (internally) to remove the lock function from the existing lever it would require the electronic lock from the other case to be fitted.

G'day Quadcam (like the nick) - welcome to the forum.

I've not had any experience modifying transfer cases - how hard a job do you reckon it would be?

Cheers,
Drew.

[quadcam Junior Member Find all posts View Profile Close quadcam]

Looking at the book and then at the car I don't think practice will be as easy as theory. But looking a 2nd and 3rd time maybe it is possible.

In the top of the regular transfer case there is the lock selector shaft with fork and beside it is the range selector shaft with fork. In the Push button lock transfer only the range selector shaft / fork is in the top and connected to the lever. The lock selector shaft / fork are situated under the main shaft and are controlled by an actuator on the rear middle of the case. If you look on the back of the case you can see the round casting with 3 undrilled holes ? in it. I was originally thinking you would have to get / fit the actuator and dissamble the case to swap the shafts / forks which would probably be uneconomic $ wise.

But, on looking at how the current transfer lever works you see that in the 4H position the lever is to the left which (after going through a pivot) means it is engaged into the right hand selector shaft (the lock selector). When you push the lever forwards you move the lock selector shaft back and lock the centre diff. But in this position the transfer lever is now gated and can move to the right to engage with the range selector shaft (however there is a spring bias to keep the lever on the left side in the lock selector shaft). If you move the lever to the right and engage the range shaft you can then move it from the H range thru neutral and into the L range position. But you have left the lock selector shaft in the locked position. If the lock selector shaft can be re-engaged from the L range position it may be possible to pull the lever back and disengage the lock. The shift pattern would then be H4 - H4L - N - L4L - L4 and back again, messy but better than nothing?

However, it needs more investigation, at least the centre console out and lever out of the top of the case to see how it engages the shafts. Ultimately it would require the lock shaft out to have another set of fingers fitted to engage from the L4L position but there may be other physical things that would preclude it ever happening. If it is possible I think it would be cheaper than the first alternative. If I have time on the weekend I will have a look around.

[jeff s Avid PP Poster! Find all posts View Profile Close jeff s]

I would be interested in that also.

I used to have a suzuki sierra and you could achieve low ratio 2WD.
You would just leave the front hubs out.

I would like the option of Low 2WD with the prado. Mainly at the boat ramp.
At the moment I lock in low to clear the water without to much clutch slip and then hope the lock drops out quick when I go back to normal. as I'm driving to the derigging area.

jeff.

[Guest Close Guest]

On my previous vehicle (surf) I fitted freewheeling hubs to the front and simply left them disengaged so that I had L/R but only rear wheel drive

Gill

[xvprado Senior Member Find all posts View Profile Close xvprado]

Buy a VX ?
CDL is electronically actuated

[quadcam Junior Member Find all posts View Profile Close quadcam]

Yes, but VX are auto only, so if you want a manual a VX is not an option.