Chrysler 8.25 Rear Differential Master Bearing Kit, Timken

If the rear axle under a 2005-or-newer Jeep with the Chrysler 8.25 (C213R or C213RE) has started to whine on the highway, hum louder on coast than on throttle, or weep gear oil past the pinion seal, the bearings are usually the real problem. The Motive Gear R8.25RJLMKT is the master bearing kit for that later-style 8.25: Timken carrier and pinion bearings plus every seal, sleeve and bolt you need to set the axle up correctly once it is apart. It is the kit to buy for a bearing job, a regear, or a locker install on these axles.

What the master bearing kit does in a Chrysler 8.25

The 8.25 is a C-clip semi-float rear. The pinion rides on two tapered roller bearings, front and rear, held in preload by a crush sleeve (or a shim pack) and the pinion nut. The carrier spins on two more tapered bearings in the housing saddles, and shims behind them set both carrier preload and ring gear backlash. When any of those four bearings wears, the pinion moves under load, the contact pattern walks off the teeth, and the gears start to sing. Replacing all four at once, with a new crush sleeve, seal and ring gear bolts, puts the whole gear train back on a fresh, known baseline.

Symptoms of worn 8.25 bearings

• A steady whine or howl that rises with road speed and changes pitch between accelerating and coasting
• A rumble or growl from the center section that does not change much when you load or unload the throttle (carrier bearings)
• Gear oil on the pinion yoke and the bottom of the housing, a sign of pinion end play chewing up the seal
• Clunk on take-off or a loose feel at the yoke when you rock it by hand
• Metallic glitter or bearing flakes on the cover magnet or in the drained oil

How to confirm the bearings are the problem before buying

Drain the oil and pull the cover. Glitter is normal; chips or flakes are not. Grab the pinion yoke and try to move it up, down and in and out: any clunk means pinion bearing preload is gone. With a dial indicator on a ring gear tooth, check backlash and rock the carrier side to side to feel for carrier bearing play. Paint a few teeth with marking compound and look at the pattern. If the pattern is sound and only the bearings are loose, this kit is the fix. If the teeth are pitted or chipped, plan on new gears too. Many 8.25 ring and pinion sets are cut for the 2004-and-older axle, so ask us to match a set to your C213R or C213RE before ordering.

Fitment

Catalogs list R8.25RJLMKT as the Chrysler 8.25 Jeep kit for 2005-2013, the later axle family Chrysler coded C213R and C213RE (some catalogs call it the 8.375). The Jeep Liberty is the most common vehicle buyers bring us. The 1976-2004 Chrysler 8.25 (Cherokee XJ, older Dakota and Durango, 1997-2004 Ram 1500) uses different bearings, so it needs the 1976-2004 Chrysler 8.25 overhaul kit or the USA Standard 76-04 kit instead. Read the axle tag, or measure your old bearings and race numbers, and if you are unsure send us the year and VIN before you order. More axle parts are in our hard parts category.

Install notes

• Pull the axles: remove the cover, the pinion shaft lock bolt and pinion shaft, push the shafts in and remove the C-clips.
• Mark the bearing caps, remove the carrier, then the pinion. A clamshell or split-plate puller saves the new bearings from damage; the OTC 4520 side bearing puller handles the carrier bearings.
• Drive in the new pinion races, set pinion depth with the shims, and press the rear pinion bearing on.
• Install the new crush sleeve, seal and nut, then tighten in small steps while reading rotating torque with an inch-pound wrench. Revolution Gear's published 8.25 figure is 12-15 in-lb for new bearings. Overshoot and the sleeve must be replaced.
• Press on the carrier bearings, set backlash at .006-.010 in, and torque ring gear bolts to 55 ft-lb and bearing caps to 60 ft-lb (Revolution Gear chart). Read the pattern with the supplied compound before sealing the cover.
• Refill with the gear oil grade in your owner manual and add friction modifier if the axle has a clutch-type limited slip.

Will this kit fit my 1999 Jeep Cherokee XJ 8.25?

No. The XJ and other 1976-2004 Chrysler 8.25 axles use a different bearing set. R8.25RJLMKT is the 2005-2013 Jeep kit for the C213R and C213RE. For the older axle, use one of the 1976-2004 Chrysler 8.25 overhaul kits in our store.

What is in the R8.25RJLMKT box?

Timken tapered carrier bearings and races, Timken front and rear pinion bearings and races, crush sleeve or preload shim pack, pinion nut, pinion seal, 10mm ring gear bolts, cover gasket, shims, marking compound with a brush, and RTV.

Can I reuse my old crush sleeve?

No. A crush sleeve is a one-time part. Once it has been crushed it will not hold preload correctly, which is why a new one is in the kit. If you overtighten the new sleeve while setting preload, it has to be replaced again.

Do I need a new ring and pinion with this kit?

Only if the teeth are damaged or you are changing ratio. Bearing whine on its own is cured by this kit. If the teeth are pitted, chipped or blued, replace the gears at the same time since the axle is already apart.

What gear oil goes back in the 8.25?

Use the grade listed in your owner manual or on the axle tag. If the axle has a clutch-type limited slip, add limited-slip friction modifier unless the oil already contains it.

Is this a job I can do at home?

If you have a press or bearing pullers, a dial indicator and an inch-pound torque wrench, yes. Setting pinion depth, preload and backlash is the part that takes care. Without those tools, a driveline shop can install the kit.