Currie offers many different types of housing center sections. Thecenter section chosen will vary according to appearance, and how muchpower is expected. At the top is an early-Ford-style housing from1957-1966. Center and bottom are 1967-and-up, with the ring gear bulge,using larger diameter axletubes.
We have a friend who is building a '67 Fairlane restomod. He has decidedthe original 8-inch axle isn't going to cut it with the larger engine hehas planned.
He wants a 9-inch axle, but he doesn't have any parts to build one. Hecould comb the boneyards looking for a complete Ford axle with a nodulariron gear case, but the chances of finding one are slim. Evengarden-variety axle housings with the gray-iron cases have becomescarce. Used to be you had to go with a high-dollar aftermarket case andeither a junkyard or custom-made housing if you wanted the strength andreliability that the big Ford axle offers. However, with theintroduction of the new Currie 9-Plus line of axle components, it's nowpossible to build a complete Ford 9-inch axle, using all Currie parts.One of the best things about 9-Plus parts is the gear carrier, which issuperior in strength to either the Ford gray-iron or nodular-iron cases.When compared with a stock Ford part, the Currie gear case is reinforcedwith additional webbing in crucial areas.
Here's the center section with axletubes and bearing housings. The ownerwants his axle narrowed 2 inches overall. Our tubes are cut to achievethe desired axle width when everything is assembled. | 
Once assembled, the housing joins others in a trip to the blastingcabinet. Once inside, the axlehousing will be blasted clean with steelshot. | 
Axlehousing components are assembled onto a jig--a rotisserie that canbe rotated as the welder strikes in a stationary position. The result isa nice uniform bead for 360 degrees of tubing. |
The housing is blown out and cleared of all steel shot. Each axlehousingreceives this magnet to trap any ferrous particles (metal particles)that may end up suspended in the lubricant. | 
These axles are fresh from the spline-cutting operation. They arechecked for correct length in this jig, which fits over the carrierstuds and measures axle depth into the housing. | 
We've already installed the pinion gear assembly into the Currie 9-Plusgear case. Next, it is placed on this assembly fixture that allows it tobe rotated for work on either side. |
With the ring gear already installed on the differential, it's time forinstallation. The technician is carefully holding the races in placeover the side bearings. The assembly is lowered into the differentialcase. | 
The side bearings are seated with the retainer. | 
The side-bearing cap is installed and threaded to accept the retainer.Running these retainers in or out with a spanner wrench changes thering-and-pinion backlash and mesh. This controls how deeply thering-and-pinion fit together. |