After Disassembly

DESCRIPTION
Thoroughly clean all parts. The pinion seal is fluoroelastomer and must not be cleaned, soaked or washed in cleaning solvents. Always use clean solvent when cleaning bearings. Oil the bearings immediately after cleaning, to prevent rusting. Inspect the parts for wear or damage. If rust is present, remove with a wire brush mounted on a power drill or equivalent. Rinse clean with metal-prep solvent on sponge or rag to remove all particles.

When a scored ring gear and pinion is replaced, the axle housing should be washed thoroughly. Inspect individual parts as described below.

GEARS
Examine the teeth of ring gear and pinion for scoring or excessive wear. Worn gears cannot be rebuilt to correct a noisy condition. Gear scoring is the result of excessive shock loading, vehicle loading, or the use of an incorrect lubricant, all of which contribute to the loss of lubricating film between the two gears. Scored gears cannot be reused. Examine the teeth and thrust surfaces of the differential gears. Wear on the hub of the differential side gear can cause a chucking noise known as chuckle when the vehicle is driven at low speeds. Wear of splines, thrust surfaces or thrust washers can contribute to excessive driveline backlash.

REAR BRAKE ANTI-LOCK SENSOR
Inspect the rear brake anti-lock sensor for loose metal particles, and clean if required. Note any indication of lubricant leakage through core of rear brake anti-lock sensor or around perimeter. Replace as required.

ANTI-LOCK SPEED SENSOR RING
Examine the anti-lock speed sensor ring and make sure it is firmly pressed on to the differential case. Check it for damaged (dented, chipped or missing) teeth that could result in erratic RABS performance. If damage is found, remove and replace anti-lock speed sensor ring.

BEARING CUPS AND CONE AND ROLLER ASSEMBLIES
Check bearing cups for rings, scores, galling or excessive wear. Pinion bearing cups must be solidly seated in the housing bores. Check for seating by attempting to insert a 0.04-mm (0.0015-inch) feeler gauge between these cups and the bottoms of their bores.

When operated in the bearing cups, cone and roller assemblies must turn without roughness. Examine the large roller ends for wear. If the original blend radius has worn to a sharp edge, the bearing should be replaced.

If inspection reveals either a worn bearing cup or a worn cone and roller, both parts should be replaced to prevent damage.

UNIVERSAL JOINT FLANGE, REAR AXLE
Make sure the surfaces of the rear axle universal joint flange have not been damaged while removing the driveshaft or the rear axle companion flange from the rear axle. The end of the rear axle universal joint flange that contacts the front differential pinion bearing inner race or slinger washer, as well as the flat surface of the pinion nut counterbore, must be smooth. Polish these surfaces if necessary. Note also the barrel of the rear axle universal joint flange (half-round) for any damage which could permit the pinion seal to leak. Roughness aggravates backlash noises and causes wear of the rear axle universal joint flange and pinion nut, with a resultant loss in pinion bearing preload.

DIFFERENTIAL HOUSING
Make sure the differential bearing bores are smooth. Remove any nicks or burrs from the mounting surfaces of the differential carrier housing.

DIFFERENTIAL CASE
Make sure the hubs where the bearings mount are smooth. Carefully examine the differential case bearing shoulders, which may have been damaged when the bearings were removed. The bearings will fail if they do not seat firmly against the shoulders. Check the fit (free rotation) of the differential side gears in their counterbores.

NOTE: Care should be taken to prevent damage to the anti-lock speed sensor ring while handling and servicing the differential case.

LIMITED SLIP DIFFERENTIAL PARTS
Inspect the differential clutch packs for uneven or extreme wear. The tanged clutch plates must be free from burrs, nicks or scratches which could cause excessive or erratic wear to the internally splined clutch plates. The internally splined clutch plates should be inspected for condition of the material, and wear. Replace the clutch plates if their thickness is less than 1.5 mm (0.058 inch) or if the material is scored or badly worn. Inspect the clutch plate internal teeth for wear. Replace them if excessive wear is evident.

Clutch plates should be replaced as a set only. Examine all thrust surfaces and hubs for wear. Abnormal wear on these surfaces can contribute to a noisy rear axle.

WHEEL BEARING AND SEAL
Opposed pairs of tapered roller bearings are used on all full-floating axles, which are used on vehicles over 8551 GVW. The bearings ride on the axle housing outside the axle shaft.

The wheel seal on full-floating axles is inboard of the inner wheel bearing. It is identified as 1175 on Dana axles and 1177 on Ford 10.25-inch axles. The Dana seal lip runs against the axle spindle, while the Ford seal has internal lips running against the seal internal surface.