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Ford Mustang Rearends - Currie In A Crate
Currie's 9-Inch Rearends Are Now Available On A Crate Basis For Vintage And Fox Mustangs
Nearly 90 percent of the thousands of rearends built by Currie share some of the same parts, including the housings and axles. Other parts include the 9-Plus round-back, heavy-duty housing, as well as 31-spline axles built to the stock overall width and pinion offset specs of the car. Heavy-duty 2-1/2-inch-wide leaf-spring pads are installed in the stock location for easy bolt-in installation. The housing includes all third-member studs installed and the Torino-style, late-model, large-bearing housing ends. The axles include the stock 5-on-4-1/2-inch wheel-bolt pattern; installed wheel studs; 1/4-inch-thick, heavy-duty bearing retainer plates; and tapered, pressed-on, Timken-style wheel bearings. The crate rearends are shipped in four separate cartons, which include the housing, the third member, axles, and brakes. Basic assembly is required. Shown here are the housing, axles, and third member for the typical vintage Mustang application (PN FDM6466X for '65-'66, FDM6770X for '76-'70, and FDM7173X for '71-'73).
For decades, the Ford 9-inch rearend has been the standard by which all other axles are judged. First introduced in 1957, it was used throughout the entire '65-'73 vintage-Mustang era on cars with optional higher-output engines available, beginning with the K-code Hi-Po 289s in the first '64-1/2s.
For '66, K-code cars were the only Mustangs equipped with the 9-inch axle. For '67, cars equipped with a 390 joined in. From that point forward, mainly '68-'73 big-block (390, 428, and 429) Mustangs were equipped with a 9-inch. Cars with 351Ws and 351Cs also got this legendary piece of hardware. The only small-block Mustangs to get a 9-inch were '69-'70 Boss 302s and the previously mentioned '65-'67 K-codes. Mustangs with 289s and 302s were equipped with an 8-inch rearend.
It's acceptable to say that high-performance Mustangs and 9-inch rearends go together like ham and eggs-it's a fact not lost on Currie Enterprises. The company has implemented a crate rearend program to reduce the time needed to ship one. Instead of waiting several weeks for it to be custom-built and shipped, Currie can get one out the door in a day or two. Roughly 85-90 percent of the custom-ordered rearends share the same housings and axles, along with other components and parts common to Mustangs. The company keeps these across-the-board pieces on the shelf before a rearend is ordered. The program will be of real interest to Mustang owners who want to upgrade.
Along with vintage cars, Currie offers applications for part of the late-model spectrum. This includes '79-'93 Fox-body cars, as well as a complete and assembled package for '05-'07s.
In addition to vintage cars, the crate rearends are also available for '79-'93 Fox Mustangs. Those years use this 59-1/2-inch-wide housing. Included are the required stock suspension brackets installed to accept the Fox Mustang's upper and lower control arms. Urethane upper control arm bushings are also installed in the upper control arm housing brackets. For four-lug Fox applications, order PN FDM7993X4; five-lug setups are PN FDM7993X5. The crate rearend program doesn't cover SN-95 ('94-'04) Mustangs because they use a wider 60-3/4-inch ('94-'98) or 61-1/4-inch ('99-'04) housing. It's not possible to integrate the SN-95's internally mounted ABS sensor system, which is inside the centersection of SN-95 8.8 rearends. A 9-inch rear can be custom-ordered in the proper width for an SN-95, but it won't have provisions for ABS. That's not a problem on open-track or drag cars, or if ABS in the back isn't a priority.
A complete, ready-to-install Currie 9-inch rearend is now available for '05-'07 Mustangs. Now that S197s in supercharged or turbo-charged form are pushing the 600hp threshold, there's certainly a place for this setup. Features include a Currie 9-Plus heavy-duty housing, 9-Plus late-model large-bearing housing ends, jig-mounted factory brackets, and Currie performance axles. The rearend also retains the factory rear disc brakes and all ABS equipment. As a direct bolt-in installation, there are the usual benefits of the 9-inch design, including the easily changed third-member assembly, heavy-duty third-member upgrades, and a choice of gear ratios from 2.47 to 7.33. This package is also compatible with stock, Currectrac, or other aftermarket control arms.