FACTORY CAST IRON VS NODULAR IRON
OEM Ford 9 inch cases were originally made from cast iron.
This material was inexpensive, easy to pour, and offered acceptable strength for the time.
Later, certain applications became more demanding that required a stronger case.
More material was added in critical areas including additional webbing.
WAR cases had these structural features, but were still made with cast iron.
Since cast iron tends to be brittle, a new material was utilized for heavy duty applications.
OEM Ford 9 inch nodular iron cases incorporated other elements into the cast iron.
This created a stronger molecular bond that made the case more ductile and less prone to breakage.
This became the case of choice for heavy duty applications.
It’s denoted by an N cast above the pinion support area in between the webbing.
The factory main cap bore sizes were 2.891” and 3.062”
The 3.062″ bore uses bearings with a higher load capacity.
OEM Ford 9 3/8” case with a 3.250” bore size.
It’s appearance is very similar to a Ford 9″ case and it will bolt into the same housing.
It was available for a limited time from Ford, but pinion supports, differentials and gear sets are no longer available.
STRANGE S-SERIES NODULAR 9 INCH CASE
Strange’s radial rib design significantly increases the rigidity of the case.
Strange Engineering’s own blend of nodular iron contains more bonding additive which increases material strength by 8-10%.
With strategical reinforcements to the pinion support area, tail bearing pocket, and main caps, it exceeds the strength of the factory nodular case.
The 3.062” bore case will fit all differentials and spools from 28 to 33 spline.
The 3.250” will fit 35 spline differentials, spools and 40 spline spools that require a 3.250” bore case.
Economical pricing allows an individual to purchase a new upscale case at a price of a used and fatigued factory part.
This is perfect compliment for your Ford 9 inch rear end.
STRANGE PRO SERIES NODULAR IRON 9 INCH CASE
The Pro Series case is designed for maximum rigidity and strength where weight is not a primary concern.
It can be identified by the stout horizontal and vertical ribs. As with all Strange engineering cases, “Strange” is embossed near the main cap area.
Strange Engineering’s proprietary form of nodular iron is used, which is 8-10% stronger than typical nodular iron.
The Pro Iron case design features reinforcements to two critical areas: the pinion support area and the tail bearing pocket.
The main caps are chrome moly and utilize high strength adjuster nuts.
The 3.062” bore case will fit all differentials and spools from 28 to 33 spline.
The 3.250” will fit 35 spline differentials, spools and 40 spline spools requiring a 3.250” bore case.
