When a high pinion is installed in the rear, due to the design, the ring gear will actually be throwing the oil away from the pinion.
This will tend to starve the pinion bearings, especially the smaller, front bearing.
When i ran one the the rear of my truck, I took a fill plug and drilled a 1/4" hole in the middle of it and then installed the plug in the fill thread of a bent housing. By using a hole saw, i was able to cut out the 18x1.50 mm seat and then welded it in the top of the rear end housing.
After filling the rear end to the factory fill hole, I removed the top plug and added an additional pint more.
Dean, my salesman, is running high pinions front and rear on his 85 truck.
Marlin
