http://www.polyperformance.com/shop/...t-p-20131.html

Anybody seen these before? Any experiences? I'm kind of interested in the clearance gained. They are very pricey, but for some extreme off road when 5" of additional axle clearance would make a difference, this looks about right.

From the site...

Performance:
Four gear design – no reverse rotation gearing required (no flipped diffs!)
4.9 inch lift for improved ground clearance
1.5:1 reduction ratio for increased wheel torque without increased stress on the ring and pinion
Heavy duty vented rotor with Wilwood four piston caliper
CTIS available

Strength:
Ductile iron case for high yield strength and toughness
2.25 inch wide gears for maximum torque capacity and life
1.5 inch diameter/35 spline input shafts
2 inch diameter/41 spline output shafts

Flexibility:
Modular design – attachment knuckle can be removed and replaced for use with multiple axle housings
Drive/steer units use standard Dana 60 u-joint
Available in two-wheel steer or four- wheel steer configuration

 

that looks neat, i'm not sure it would be all that good for hwy use, but sure would be a big advantage off road, and from the pics, it looks like its for the older king pin 60's