The rear axle assembly is a hypoid semi-floating type, featuring a differential carrier made from casting with a pressed steel cover, while the axle tubes are constructed from steel, pressed and welded into the carrier. An optional Traction-Lok limited slip rear axle is available, which operates normally until one wheel loses traction, utilizing multi-disc clutch packs and a speed-sensitive engagement mechanism to lock both axleshafts together, providing equal rotational power to both wheels. Knowing the axle identification number, located on a small metal tag near one of the cover bolts, is crucial for certain operations, especially when replacing the axleshafts. Often, issues suspected in the rear axle area may actually originate elsewhere, so a thorough check is advisable before concluding a rear axle problem. Common noises associated with rear axle diagnosis include road noise, which can be mistaken for mechanical faults and remains consistent regardless of vehicle power; tire noise, which can arise from worn or under-inflated tires and remains constant during various driving conditions; and engine and transmission noise, which can mislead diagnostics as it travels along the driveline. To isolate such noises, noting the engine speed at which the noise is most pronounced and then running the engine in Neutral at the same speed can help determine if the rear axle is at fault. Overhaul and general repair of the rear axle require special tools and critical measurements, making it beyond the scope of the home mechanic, with procedures involving axleshaft removal and installation, oil seal replacement, bearing replacement, and complete unit removal for repair or replacement.