Yukon Gear Master Overhaul Kit for 2014+ RAM 2500 AAM 11.5in

The coil-spring Ram 2500 that arrived for 2014 carries an American Axle 11.5 in. rear end behind the Cummins, HEMI and gas V8 trucks alike. Hauling and towing with big tires is hard on its bearings, and owners usually notice it as a highway whine that was not there before, a growl under load, or a damp pinion seal. The Yukon Gear & Axle YK AAM11.5-C master overhaul kit is the complete bearing, seal and shim set for rebuilding that axle, whether you are keeping the factory gears or installing a new ratio. It is new, part number YK AAM11.5-C.

What this kit does in the 2014-up AAM 11.5

Inside the 11.5 the pinion is supported by an inner and an outer tapered roller bearing, preloaded with a crush sleeve and pinion nut, while the carrier rides on two side bearings positioned by shims. Those four bearings decide where the pinion and ring gear meet. As they wear, the mesh moves, noise climbs and tooth wear speeds up. The gears used in the 2014-up Ram 2500 axle have a 2.125 in. inner and 2.000 in. outer pinion bearing journal, larger than the earlier small-bearing 11.5 gears, and this kit is matched to that bigger pinion. It contains Timken carrier bearings and races, Timken pinion bearings and races, a pinion seal, a complete shim kit, a pinion nut, a crush sleeve, oil baffles and slingers where the axle uses them, thread locking compound, marking compound with a brush and a cover gasket.

Symptoms of a worn 11.5 in a 2014-up Ram

• Whine between roughly 45 and 70 mph that rises or falls as you go on and off the throttle.
• A rumble with a trailer hitched that fades when the truck is unloaded.
• A clunk through the floor when shifting into gear or taking off, with play at the yoke.
• Gear oil on the pinion seal, the yoke or the crossmember above it.
• Gray, metallic oil or heavy paste on the cover when it comes off.

How to confirm before you buy

Support the truck on stands with the rear wheels off the ground and drop the driveshaft at the pinion yoke. Spin the pinion by hand: roughness or a notchy feel points to the pinion bearings, and any in-and-out movement means preload is lost. Drain the oil, pull the cover and check the ring gear teeth with marking compound. Clean, unbroken teeth mean an overhaul with this kit is the right repair; pitted or chipped teeth call for new gears too. Also rule out a dry axle-end wheel bearing, tire noise from aggressive tread and a worn driveshaft center bearing before tearing into the center section.

Fitment

Our listing covers the 2014-and-up Ram 2500 with the AAM 11.5 in. rear axle. Retail application data most often lists 2014-2018 Ram 2500, and some catalogs narrow it further by trim, so confirm the axle before ordering. The key check is the gear: this kit is for 11.5 in. gears with 2.125 in. inner and 2.000 in. outer pinion journals. 2011-2013 Ram 2500 and leaf-spring 3500 axles use the Yukon YK GM11.5-B, and 2019-up Rams use the Yukon YK AAM11.5-E. Send us your year, model and VIN if you want a second check, or see every axle kit in our rebuild kits collection.

Install notes

• Mark the carrier bearing caps side to side before you pull them, and keep the original side shims together as a baseline.
• Press new races fully home and lubricate the bearings with gear oil, not grease, during setup.
• Install the new crush sleeve and tighten the pinion nut gradually, checking rotating torque between steps; if you overshoot preload, a new sleeve is required.
• Use the marking compound to verify the pattern and set backlash with a dial indicator before final torque on the cap bolts.
• Seal the cover with the supplied gasket and fill with the gear oil grade and capacity in your owner's manual, including friction modifier if your axle has a limited-slip carrier.

Re-gearing for bigger tires is the most common reason to do this job: pair the kit with the Yukon 4.88 ring and pinion for the 2014-up Ram 2500, and protect the rebuilt axle with the Yukon Hardcore 11.5 diff cover.

Will this kit fit my 2014-2018 Ram 2500?

It is built for the AAM 11.5 in. rear axle in the 2014-and-up Ram 2500 with gears that have 2.125 in. inner and 2.000 in. outer pinion bearing journals. Most catalogs list 2014-2018; send us your VIN and we will confirm the axle.

Does it fit a 2019 or newer Ram?

Use the Yukon YK AAM11.5-E for 2019-up Ram AAM 11.5 rear axles. The YK AAM11.5-C is for the 2014-up Ram 2500 axle.

Can I use this kit when I re-gear to 4.88 or 5.13?

Yes. A master overhaul kit is what you install with new gears, as long as the new ring and pinion has the 2.125 in. / 2.000 in. pinion journals this kit is matched to. Most new 11.5 gear sets use that size.

What is in the box?

Timken carrier bearings and races, Timken pinion bearings and races, a pinion seal, a complete shim kit, a pinion nut, a crush sleeve, oil baffles and slingers where applicable, thread locking compound, marking compound with a brush and a gasket.

What gear oil does it take after the rebuild?

Use the gear oil grade and capacity in your Ram owner's manual for the rear axle, and add friction modifier only if your axle has a limited-slip carrier that calls for it. Break in new gears gently, avoiding heavy towing for the first few hundred miles.