Axles

Front and Rear Axle Assembly

A complete axle assembly includes the axle housing, carrier/differential, and axle shafts as one unit. This is the most cost-effective approach when multiple components within the axle are worn or damaged. Not included: driveshaft, wheel bearings, brakes, or mounting hardware.

Gear ratio must match. The front and rear axles on 4WD vehicles must share the same gear ratio (e.g., both 3.73:1). Mismatched ratios cause drivetrain binding and damage the transfer case. The axle ratio is typically stamped on a tag on the differential cover or can be verified by rotating the driveshaft and counting wheel turns.

Positraction / limited-slip. If your original axle had a limited-slip differential, your replacement must too — or you'll lose traction performance. Check the axle tag or RPO codes on the door sticker to confirm whether your original had limited-slip.

Axle Housing

The axle housing is the structural tube-and-center casting that carries the differential and axle shafts on a solid-axle vehicle. It is sourced when the housing itself is bent or cracked but the internals are good. Confirm the housing width, spring perch locations, and brake/sensor mounting points match your vehicle.

Axle Shaft

The axle shaft transmits torque from the differential to the wheel. Used axle shafts are a reasonable value when the shaft itself is undamaged (not twisted or bent). Check the splines at both ends for wear and verify the shaft length and flange bolt pattern match your axle housing.

Loaded Beam Axle

A loaded beam axle is a complete rear beam (twist-beam or solid axle) supplied with brakes, bearings, and hubs already installed — common on the rear of front-wheel-drive cars. Buying it loaded saves significant labor. Confirm the axle width, mounting bushing positions, and brake type (drum vs. disc) match your vehicle.

Independent Rear Suspension Assembly

IRS assemblies are the complete rear axle module including subframe, control arms, and differential. These are typically sourced when rebuilding a vehicle with major rear-end damage. Confirm subframe mounting points match your chassis before purchasing — body variations within a model line sometimes differ.

The differential allows wheels to turn at different speeds in corners while still receiving drive torque. The carrier assembly houses the ring gear, spider gears, and side gears.

Differential Assembly

When buying a used differential assembly:

• Confirm the ring gear tooth count (determines gear ratio)

• Check for scoring or pitting on the gear faces

• Verify clutch pack condition on limited-slip units (rough engagement indicates worn clutches)

Match the differential assembly to the gear ratio family, axle model, and limited-slip vs. open configuration.

Carrier Assembly

The carrier assembly is the complete internal gear package — case, ring gear, spider gears, and side gears — that drops into the axle housing. Match it to your axle model, gear ratio, and limited-slip vs. open configuration.

Ring Gear & Pinion

Ring & pinion sets must always be replaced as matched pairs — never mix ring gears and pinions from different sets. The ring and pinion are lapped together at the factory; mismatched sets run noisily and wear quickly. Match the tooth count to your desired gear ratio and the axle model.

Front and Rear Drive Shaft

Driveshafts are balanced assemblies — a dent, repair weld, or out-of-spec U-joint causes vibration at speed. When sourcing a used driveshaft, inspect for straightness (roll it on a flat surface), check U-joint play, and confirm the length and yoke size match your application.

Transfer Case Assembly

The transfer case splits power between front and rear axles and provides high/low range in 4WD vehicles. Transfer cases are specific to transmission output shaft size and bolt pattern — even within the same vehicle family, different transmission/transfer case combinations require matching units. Confirm by the transfer case model number (stamped on the case or on an ID tag).

Transfer Case Motor

The transfer case motor (encoder motor) shifts the transfer case between 2WD, 4WD high, and 4WD low electronically and is separate from the case itself. A failed motor leaves the vehicle stuck in one mode. Match the motor to the transfer case model and connector type.