Everything needed to reset a Chrysler 9.25 rear axle: Koyo carrier and pinion bearings, crush sleeve, full shim kit, seal, ring gear bolts.
If your Ram 1500, Dakota, Durango, Aspen or Mitsubishi Raider has started to howl on the highway, clunk on and off the throttle, or leave gear oil on the driveway behind the pinion, the 9.25 inch rear axle is asking for new bearings. This master overhaul kit is the USA Standard Gear ZK C9.25-R-B package for the 2001-2009 Chrysler 9.25 rear: Koyo bearings and races for both the carrier and the pinion, plus every seal, shim, sleeve and fastener you have to replace once the carrier is out.
The 9.25 carries its pinion on two tapered roller bearings separated by a collapsible crush sleeve. Tightening the pinion nut crushes the sleeve until the bearings reach their running preload, and a shim behind the inner bearing sets how deep the pinion sits in the ring gear. The carrier rides on its own pair of tapered bearings in the housing. When any of these bearings wear, preload drops, the pinion walks under load, and the ring and pinion contact pattern moves off center. That is where the whine comes from, and it gets worse fast because the gears start wearing to the bad pattern. Rebuilding with all new bearings, a fresh sleeve and new shims puts the geometry back where the gears expect it.
Drivetrain noise is easy to blame on the wrong part. Jack up the rear, grab the yoke and feel for in-and-out play, then spin the wheels and listen. Our guide on differential whine on acceleration versus deceleration helps separate pinion bearing noise from gear wear, and transmission versus differential noise covers the other common mix-up.
The kit is made for the 2001-2009 Chrysler 9.25 inch rear. Our listing covers the Ram 1500 and Dakota through 2010, Durango 2001-2009, Aspen 2006-2009, Ram Van 1500 and 2500 2001-2003, and Raider 2006-2009. You can spot this axle by its 12-bolt, octagonal stop-sign shaped cover; it uses a 1.875 inch pinion, a 29-spline yoke and 31-spline axle shafts. It does not fit the ZF-designed 9.25 used on later coil-spring Ram 1500s, which has a cover with two bump-outs and metric ring gear bolts; that axle takes the 2011-up ZF 9.25 overhaul kit. A 2000-and-older 9.25 needs the 2000-down kit. The 9.25 front axle on heavy-duty trucks is a different unit. For a 2010 truck, read the axle tag and send us the VIN if you are unsure.
If you are upgrading the carrier at the same time, the Detroit Truetrac for the 9.25 drops in during the same setup.
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The 2001-2009 Chrysler 9.25 rear in the Ram 1500, Dakota, Durango, Aspen, Ram Van 1500/2500 (2001-2003) and Mitsubishi Raider. Our listing extends Ram 1500 and Dakota to 2010; check the axle tag on a 2010 truck.
No. The ZF-designed 9.25 on later coil-spring Ram 1500s uses different bearings and metric ring gear bolts. It has a cover with two bump-outs and needs the ZF-specific kit.
Yes, if the gear teeth are not pitted or chipped. Note the original backlash and pattern before teardown and set the gears back to the same pattern with the new bearings.
The crush sleeve sets pinion bearing preload and can only be crushed once. Reusing it leaves the pinion loose, which is the most common reason a rebuilt axle starts whining again.
A press or bearing puller for the races, an inch-pound torque wrench for pinion preload, a dial indicator for backlash, and a long breaker bar to crush the sleeve.
