Hey h0nke, long time no see,
Check out this site:
http://home.4x4wire.com/erik/diffs/The High Pinion mounts the pinion above the center-line of the ring gear as apposed to slightly below it. Because of this, a reverse pattern gear set must be used with the High Pinion Diff.
The Benifits are that the pinion is up and away from rocks, and so is the drive shaft.
Definately an excellent upgrade choice
As far as I know, Marlin was the first person to discover that the High Pinion could be fitted to a modified Hilux housing, and at that time, he was running High Pinions in the front and rear of his rig. However, with the High Pinion mounted in the rear, the oil pump is now spun in the reverse direction, and the bearings will over heat.
So the High Pinion can only be safely used in the front, unless you are building a trail-only rig that wont see speeds over about 30 mph for any prolonged time periods.
BigMike
