Witches hat shares oil with the differentials and t-case. If you look at the number of sealing surfaces on the witches hat I am amazed they keep as much gear oil in them as they do. If your driveline gear oil does not look like fluid you drained then you dodged a bullet. That coloration is strange could be water or brake fluid contamination.
Here is a differential semi-cut-away. There are seals all over the place. Witches hat to the differential housing, locker/4x4 switch, locker/4x4 switch housing, shaft seal, two O-rings on the locker spring piston/assembly and an O-ring at the top of the shaft for the locker/4x4 fork. On top of that there is a vent hole on the top of the witches hat. I think that is most of it.
- 17424827_1281165648638419_1147498703215691842_n.jpg (82.93 KiB) Viewed 3749 times
This is a picture with the locker/4x4 slave cylinder removed looking into the differential. That black stuff is gear oil which made its way out of the differential/witches hat assembly over a period of time. On this truck is was so bad it eventually contaminated the parking brake. If you have a weepy driveline slave cylinder or switch cover you more than likely have gear oil leaking from a differential/witches hat assembly. Could be minor and just accumulated over time and needs to be drained or more serious.
- Pinzgauer Park Brake Oil Contamination (11).JPG (669.21 KiB) Viewed 3749 times
- Pinzgauer Park Brake Oil Contamination (9).JPG (615.05 KiB) Viewed 3749 times
Have had trucks in the past with enough gear oil in the central tube the driveshaft was actually rotating in it causing driveablity power issues. Very rare.
A trend (very small) if can say that with such a small population of trucks but a couple customers who regularly park/store their trucks on an incline had more of a problem with this kind of issue. Those differentials are open to the witches hats which if on an incline/decline allows the gear oil level to rise in the witches hat. Different axles are effect if stored with the truck pointed up hill or down hill. More of an issue with some of the terrain in the Bay Area.
Cheers,
Scott