Nissan Patrol 4x4 (Africa)

While lounging under the rear diff I noticed a hydrolic switch on top of the diff. If seems to be some type of adjuster for load. If the diff moves upwards the lever on the switch changes position. What does it do? I will post pics later if my description was not enough.

That would be the load compensator valve that regulates the amount of brake effort generated by the rear brakes according to the load in the rear (as measured by rear suspension deflection).

Gerrit, would that not increase braking across the entire brake system?

Will only increase brake effort in the back and set-up should be adjusted for lifted suspensions.

This load adjusters is implemented to prevent the rear brakes from locking up and having the back-end passing you while the car has no load on the rear axle.
This valve only increase the force passed through to the rear brakes as the load is increased.
This has no effect on the front braking force.
As Andries indicated the adaption of this valve is in many cases missed when a lift is done.
Then the owner wonder why the rear brakes does not wear.
Purely because it is never activate/utilized.
Bruin Beer

Interesting... I have never heard of that on a vehicle before. Surely ABS does that?

Anyway the brakes on the patrol are fantastic. I had an emergency brake situation and she pulled up neatly with no dramas!!

No, the older style ABS does not have electronic brake force distribution functionality. The old style ABS will still prevent wheel lock-up, but that is not really the point: in order to get the best possible brake performance, the brake force at each axle needs to be in proportion to the vertical load on the axle...

Roger. Makes sense.