Rear Axle Housings

What Does a Rear Axle Housing Do?

A rear axle housing is the structural shell that keeps your differential, axle shafts, and wheel bearings aligned. It also carries vehicle weight, locates the suspension, and gives your brakes a mounting point. If the housing flexes or bends, gears wear fast and axles can bind.

Housings use one of two basic designs. In a semi-floating setup, the axle shaft drives the wheel and also supports vehicle weight at the outer bearing. In a full-floating setup, the hub rides on bearings mounted to the housing tube, so the shaft only transmits torque.

Our full-floating axle guide explains why heavy trucks and many race cars use that design. Knowing which one you have narrows your parts search fast.

The housing works as part of a system. It has to match your performance axle shafts for spline count and length, and it has to accept your center section. Browse all differentials and rear end components when you're planning a full rear end build.

Types of Axle Housing Components

Axle housing components fall into three groups: ends that locate the bearings, braces that stiffen the tubes, and service parts that keep the rear end sealed. Many builds need parts from all three.

Here's what you'll find in this category:

• Axle housing ends for Big Ford, Small Ford, Small GM, Large GM, Oldsmobile, Pontiac, and Mopar rear ends, including Moser Engineering ends.
• Housing braces for the Mopar 8-3/4" rear end, plus a chromoly brace for 1979-04 Mustang and LPW tube brace kits.
• Complete rear end housing and axle packages, such as a package for the 1982-92 Chevy Camaro.
• Axle housing floater kits that let you adjust rear end height.
• Differential vents and breathers, including a push-in vent for 1962-1988 GM differentials.
• An empty differential case for GM 10.5-inch 14-bolt rear ends, with complete differential carriers listed separately.
• Brake backspacing axle sleeves for 28- and 31-spline axles.
• Emergency brake rear hub assemblies for Ford 9-inch rear ends.

How to Choose Axle Housing Ends for Your Rear End

Choose axle housing ends by matching your housing type, axle bearing size, and brake flange pattern. The ends set the bearing size and the brake bolt pattern, so a mismatch means the bearing won't seat or the brakes won't bolt up.

Start by confirming what you have. Check for an ID tag, count the cover bolts, and compare the housing shape. Our guide on how to identify a rear axle assembly walks through each step.

For a Ford 9-inch housing, you'll pick between Big Ford and Small Ford bearing sizes. Big Ford ends come in old-style and new-style (Torino) flange patterns, while Small Ford ends suit early Mustang builds. GM choices include Small GM and Large GM Impala/truck ends, some with back plates and caliper brackets.

Oldsmobile, Pontiac, and Mopar ends are also available for custom housings and swaps, including ends from Strange Engineering and Meziere. Before you order, confirm the ends match your axle bearings and the brake kit you plan to run.

When to Add a Housing Brace or Tube Brace

Add a housing brace or tube brace when your rear end sees high torque from hard launches, sticky tires, or big power. Under load, axle tubes can flex, which shifts gear contact and pinion angle. Over time, that flex can bend the housing.

Braces tie the tubes to the center section to add rigidity. Options here include a back brace for the Mopar 8-3/4" housing, tube brace kits, and a chromoly axle brace for 1979-04 Mustang. Chromoly gives you high strength without the extra weight of a heavier steel brace.

Many braces weld in place, so plan the job carefully. Welding heat can pull a housing out of line, which is why fabricators use rear end line-up tools like those from Mittler Bros. to keep the ends true.

After the work is done, recheck your pinion angle. Our guide to setting driveline angle shows how to measure it. For a drag car on slicks, a brace is cheap insurance against a bent housing.

Complete Rear End Housing and Axle Packages vs. Individual Parts

Buy a complete package when you want a matched rear axle assembly, and buy individual parts when you're repairing or upgrading what you have. Packages take the guesswork out of width, bearing size, and axle length.

Currie is a go-to source for rear end housing and axle packages. Complete packages, like one for the 1982-92 Chevy Camaro, sit at the top of this category's price range at over $2,000.

Individual parts make sense if your housing is straight and you only need ends, a brace, or a vent. They also suit builders who want a custom width or a specific center section. With a Ford 9-inch housing, add one of our Ford 9-inch third members. Then pick ring and pinion gears for your tire size and cruise RPM.

If you need more strength, a Dana 60 axle housing or 12-bolt rear end housing is a common step up. Shop Rear Axle Housings Now, and use Add a Vehicle to confirm fit before you order.