The Alloy USA rear replacement shafts for our Chrysler 8.25 axle offer the same spline count as the stock shafts but are manufactured from 1541 H high-grade alloy steel. The shafts receive the same double heat-treating as the chrome-moly front shafts and are said to be 35-percent stronger than stock. Alloy USA replacement rear axleshaft kits include new bearings, seals, and wheel studs, and offer a 5-on-4-1/2-inch single bolt pattern. The replacement axleshafts can be installed with the stock carrier or an aftermarket locker, such as an ARB Air Locker. If installing a new locker, this is a good time for pre-'97 Cherokees with the 27-spline 8.25 rear axle to upgrade to 29-spline shafts. For Cherokees with Dana 35 rear axles, Alloy USA offers its Grande 35 kit, with all the same great benefits of its other Grande kits.
Since we'd be increasing tire size to 33x12.50 in the coming weeks, we opted to replace the stock gears with 4.56-ratio ring-and-pinion gears from Precision Gear. The 4.56 gears will offer ample low-end power while still maintaining highway speeds. Precision Gear also supplied a Master Installation Kit.
For installation of the Alloy USA, Precision Gear, and ARB components, we looked to the qualified crew at the FourXDoctor in Burbank, California. The FourXDoctor offers full 4x4 service and repair along with custom fabrication, including rollcages, shock mounts, body armor, bumpers, and more. FourXDoctor also manufactures a line of rocker guards and fuel-tank skidplates for Jeep vehicles and differential guards for many axle applications.
Here is one of the stock Chrysler 8.25 rear axleshafts shown with the new Alloy USA replacement shaft. The Alloy USA shafts offer more material around the bell of the shaft and have a thicker flange than stock. They also appear not to neck down toward the splines as much as the stock 8.25 shafts seem to. | 
With the interior of the axlehousing thoroughly cleaned and inspected, the new pinion race was installed. | 
The new bearing was pressed onto the Precision Gear 4.56-ratio pinion gear. New bearings were included in the Precision Gear Master Installation Kit. |
With the Precision Gear 4.56 ring gear in place on the ARB Air Locker, we weren't able to remove the cross-shaft so the axle C-clips could be installed. It was necessary to grind down a portion of the cross-shaft and also sand down the top surface of some of the teeth on the ring gear. | 
The 8.25 diff housing was drilled and tapped to accept the supplied bulkhead fitting so the ARB could be air-actuated. | 
Alloy USA supplies new lug studs with its replacement rear-axle kits. Here the lug studs are pressed into the flange of the new axleshafts. Note the extra-thick flange, which is much larger than stock. |