Ford 9-inch rearends are ubiquitous in the world of gearheads. Even a Chevy guy could probably tell you that the 9-inch was introduced in 1957 and that the dropout-centersection design, high-hypoid gear cut, and pinion-nose bearing make it a convenient and sturdy rearend. Those are some of the reasons why car crafters with all makes of vehicles have swapped 9-inches into their cars with help from one of many shops that'll build the Ford diff in any configuration you need. But with over 40 years of stock variants and aftermarket upgrades available, it pays to know what you’re getting into when buying or upgrading a 9-inch.
That's what this story is here for. Our friends at Currie Enterprises were among the first to offer custom 9-inch diffs, and while they now handle Danas and GM 12-bolts as well, they're considered among the most knowledgeable 9-inch tuners out there. In addition to sourcing infor-mation from the catalogs of many manufacturers, we toured the Currie shop and picked their brains to provide this overview of the most common 9-inch pieces you'll have to choose from for the typical serious streeter.
